0323_c182

Unordered Tetrad Two Gene Mapping

In this problem, you will use unordered tetrads to determine the between a single pair of genes and calculate the distances between them. The yeast Saccharomyces cerevisiae is used in this study. A cross has been performed to study the linkage relationships among two genes, and the resulting genotypes are summarized in the table below.

Characteristics of Recessive Phenotypes

Gene E is linked with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene P is associated with the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

3,157

2,348

TOTAL =

5,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and P

distance =

½(95) + 3×(95)

5,600

47.5 + 285

5,600

332.5

5,600

= 0.0594 = 5.94 cM Incorrect distance =

½(2,348) + 3×(95)

5,600

1,174 + 285

5,600

1,459

5,600

= 0.2605 = 26.05 cM Correct distance =

½(3,157) + 3×(95)

5,600

1578.5 + 285

5,600

1863.5

5,600

= 0.3328 = 33.28 cM Incorrect distance =

½(95) + 3×(0)

5,600

47.5 + 0

5,600

47.5

5,600

= 0.0085 = 0.85 cM Incorrect distance =

½(2,348 + 3,157) + 3×(95)

5,600

2752.5 + 285

5,600

3037.5

5,600

= 0.5424 = 54.24 cM Incorrect distance =

½(2,348) + 3×(0)

5,600

1,174 + 0

5,600

1,174

5,600

= 0.2096 = 20.96 cM Incorrect MC

97af_0655

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene W is linked with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.
Gene Y is affiliated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

1,861

1,290

TOTAL =

3,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes W and Y

distance =

½(49) + 3×(0)

3,200

24.5 + 0

3,200

24.5

3,200

= 0.0077 = 0.77 cM Incorrect distance =

½(1,290) + 3×(49)

3,200

645 + 147

3,200

792

3,200

= 0.2475 = 24.75 cM Correct distance =

½(1,290) + 3×(0)

3,200

645 + 0

3,200

645

3,200

= 0.2016 = 20.16 cM Incorrect distance =

½(1,290 + 1,861) + 3×(49)

3,200

1575.5 + 147

3,200

1722.5

3,200

= 0.5383 = 53.83 cM Incorrect distance =

½(49) + 3×(49)

3,200

24.5 + 147

3,200

171.5

3,200

= 0.0536 = 5.36 cM Incorrect distance =

½(1,861) + 3×(0)

3,200

930.5 + 0

3,200

930.5

3,200

= 0.2908 = 29.08 cM Incorrect MC

d16d_dbc9

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is connected with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene F is affiliated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.

Set #

Tetrad Genotypes

Progeny
Count

1,840

2,895

TOTAL =

4,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and F

distance =

½(1,840 + 2,895) + 3×(65)

4,800

2367.5 + 195

4,800

2562.5

4,800

= 0.5339 = 53.39 cM Incorrect distance =

½(1,840) + 3×(65)

4,800

920 + 195

4,800

1,115

4,800

= 0.2323 = 23.23 cM Correct distance =

½(1,840) + 3×(0)

4,800

920 + 0

4,800

920

4,800

= 0.1917 = 19.17 cM Incorrect distance =

½(2,895) + 3×(0)

4,800

1447.5 + 0

4,800

1447.5

4,800

= 0.3016 = 30.16 cM Incorrect distance =

½(2,895) + 3×(65)

4,800

1447.5 + 195

4,800

1642.5

4,800

= 0.3422 = 34.22 cM Incorrect distance =

½(65) + 3×(65)

4,800

32.5 + 195

4,800

227.5

4,800

= 0.0474 = 4.74 cM Incorrect MC

bd4d_ba19

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is correlated with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene T is connected with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

170

3,708

4,322

TOTAL =

8,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and T

distance =

½(4,322) + 3×(170)

8,200

2,161 + 510

8,200

2,671

8,200

= 0.3257 = 32.57 cM Incorrect distance =

½(170) + 3×(170)

8,200

85 + 510

8,200

595

8,200

= 0.0726 = 7.26 cM Incorrect distance =

½(3,708 + 4,322) + 3×(170)

8,200

4,015 + 510

8,200

4,525

8,200

= 0.5518 = 55.18 cM Incorrect distance =

½(3,708) + 3×(170)

8,200

1,854 + 510

8,200

2,364

8,200

= 0.2883 = 28.83 cM Correct distance =

½(3,708) + 3×(0)

8,200

1,854 + 0

8,200

1,854

8,200

= 0.2261 = 22.61 cM Incorrect distance =

½(0) + 3×(170)

8,200

0 + 510

8,200

510

8,200

= 0.0622 = 6.22 cM Incorrect MC

e0d7_1154

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is analogous to the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene W is associated with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

143

3,086

3,571

TOTAL =

6,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and W

distance =

½(3,086) + 3×(143)

6,800

1,543 + 429

6,800

1,972

6,800

= 0.2900 = 29 cM Correct distance =

½(143) + 3×(143)

6,800

71.5 + 429

6,800

500.5

6,800

= 0.0736 = 7.36 cM Incorrect distance =

½(3,086) + 3×(0)

6,800

1,543 + 0

6,800

1,543

6,800

= 0.2269 = 22.69 cM Incorrect distance =

½(3,571) + 3×(143)

6,800

1785.5 + 429

6,800

2214.5

6,800

= 0.3257 = 32.57 cM Incorrect distance =

½(3,571) + 3×(0)

6,800

1785.5 + 0

6,800

1785.5

6,800

= 0.2626 = 26.26 cM Incorrect distance =

½(0) + 3×(143)

6,800

0 + 429

6,800

429

6,800

= 0.0631 = 6.31 cM Incorrect MC

fe7d_9be5

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene W is linked with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.
Gene X is associated with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

2,782

4,930

TOTAL =

7,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes W and X

distance =

½(2,782) + 3×(88)

7,800

1,391 + 264

7,800

1,655

7,800

= 0.2122 = 21.22 cM Correct distance =

½(4,930) + 3×(88)

7,800

2,465 + 264

7,800

2,729

7,800

= 0.3499 = 34.99 cM Incorrect distance =

½(88) + 3×(0)

7,800

44 + 0

7,800

= 0.0056 = 0.56 cM Incorrect distance =

½(2,782) + 3×(0)

7,800

1,391 + 0

7,800

1,391

7,800

= 0.1783 = 17.83 cM Incorrect distance =

½(4,930) + 3×(0)

7,800

2,465 + 0

7,800

2,465

7,800

= 0.3160 = 31.60 cM Incorrect distance =

½(88) + 3×(88)

7,800

44 + 264

7,800

308

7,800

= 0.0395 = 3.95 cM Incorrect MC

89cf_4018

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is connected with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene Y is associated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

1,888

1,820

TOTAL =

3,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and Y

distance =

½(92) + 3×(92)

3,800

46 + 276

3,800

322

3,800

= 0.0847 = 8.47 cM Incorrect distance =

½(1,820) + 3×(92)

3,800

910 + 276

3,800

1,186

3,800

= 0.3121 = 31.21 cM Correct distance =

½(1,820 + 1,888) + 3×(92)

3,800

1,854 + 276

3,800

2,130

3,800

= 0.5605 = 56.05 cM Incorrect distance =

½(1,820) + 3×(0)

3,800

910 + 0

3,800

910

3,800

= 0.2395 = 23.95 cM Incorrect distance =

½(92) + 3×(0)

3,800

46 + 0

3,800

= 0.0121 = 1.21 cM Incorrect distance =

½(1,888) + 3×(0)

3,800

944 + 0

3,800

944

3,800

= 0.2484 = 24.84 cM Incorrect MC

d83e_5d0f

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is linked with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene R is related to the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

168

3,796

4,636

TOTAL =

8,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and R

distance =

½(4,636) + 3×(0)

8,600

2,318 + 0

8,600

2,318

8,600

= 0.2695 = 26.95 cM Incorrect distance =

½(4,636) + 3×(168)

8,600

2,318 + 504

8,600

2,822

8,600

= 0.3281 = 32.81 cM Incorrect distance =

½(3,796) + 3×(0)

8,600

1,898 + 0

8,600

1,898

8,600

= 0.2207 = 22.07 cM Incorrect distance =

½(0) + 3×(168)

8,600

0 + 504

8,600

504

8,600

= 0.0586 = 5.86 cM Incorrect distance =

½(3,796) + 3×(168)

8,600

1,898 + 504

8,600

2,402

8,600

= 0.2793 = 27.93 cM Correct distance =

½(168) + 3×(168)

8,600

84 + 504

8,600

588

8,600

= 0.0684 = 6.84 cM Incorrect MC

0110_2900

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is affiliated with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene R is affiliated with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

4,168

3,292

140

TOTAL =

7,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and R

distance =

½(3,292 + 4,168) + 3×(140)

7,600

3,730 + 420

7,600

4,150

7,600

= 0.5461 = 54.61 cM Incorrect distance =

½(4,168) + 3×(140)

7,600

2,084 + 420

7,600

2,504

7,600

= 0.3295 = 32.95 cM Incorrect distance =

½(140) + 3×(140)

7,600

70 + 420

7,600

490

7,600

= 0.0645 = 6.45 cM Incorrect distance =

½(3,292) + 3×(140)

7,600

1,646 + 420

7,600

2,066

7,600

= 0.2718 = 27.18 cM Correct distance =

½(3,292) + 3×(0)

7,600

1,646 + 0

7,600

1,646

7,600

= 0.2166 = 21.66 cM Incorrect distance =

½(4,168) + 3×(0)

7,600

2,084 + 0

7,600

2,084

7,600

= 0.2742 = 27.42 cM Incorrect MC

b717_7142

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is correlated with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene M is related to the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

4,158

4,034

208

TOTAL =

8,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and M

distance =

½(4,034) + 3×(208)

8,400

2,017 + 624

8,400

2,641

8,400

= 0.3144 = 31.44 cM Correct distance =

½(4,158) + 3×(208)

8,400

2,079 + 624

8,400

2,703

8,400

= 0.3218 = 32.18 cM Incorrect distance =

½(0) + 3×(208)

8,400

0 + 624

8,400

624

8,400

= 0.0743 = 7.43 cM Incorrect distance =

½(208) + 3×(208)

8,400

104 + 624

8,400

728

8,400

= 0.0867 = 8.67 cM Incorrect distance =

½(4,034) + 3×(0)

8,400

2,017 + 0

8,400

2,017

8,400

= 0.2401 = 24.01 cM Incorrect distance =

½(208) + 3×(0)

8,400

104 + 0

8,400

104

8,400

= 0.0124 = 1.24 cM Incorrect MC

19c9_b8eb

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is linked with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene F is associated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.

Set #

Tetrad Genotypes

Progeny
Count

230

4,440

4,530

TOTAL =

9,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and F

distance =

½(0) + 3×(230)

9,200

0 + 690

9,200

690

9,200

= 0.0750 = 7.50 cM Incorrect distance =

½(230) + 3×(0)

9,200

115 + 0

9,200

115

9,200

= 0.0125 = 1.25 cM Incorrect distance =

½(4,530) + 3×(0)

9,200

2,265 + 0

9,200

2,265

9,200

= 0.2462 = 24.62 cM Incorrect distance =

½(230) + 3×(230)

9,200

115 + 690

9,200

805

9,200

= 0.0875 = 8.75 cM Incorrect distance =

½(4,440) + 3×(230)

9,200

2,220 + 690

9,200

2,910

9,200

= 0.3163 = 31.63 cM Correct distance =

½(4,440 + 4,530) + 3×(230)

9,200

4,485 + 690

9,200

5,175

9,200

= 0.5625 = 56.25 cM Incorrect MC

0ba0_0eb9

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is associated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene P is analogous to the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

3,152

2,352

TOTAL =

5,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and P

distance =

½(3,152) + 3×(0)

5,600

1,576 + 0

5,600

1,576

5,600

= 0.2814 = 28.14 cM Incorrect distance =

½(0) + 3×(96)

5,600

0 + 288

5,600

288

5,600

= 0.0514 = 5.14 cM Incorrect distance =

½(2,352) + 3×(96)

5,600

1,176 + 288

5,600

1,464

5,600

= 0.2614 = 26.14 cM Correct distance =

½(2,352 + 3,152) + 3×(96)

5,600

2,752 + 288

5,600

3,040

5,600

= 0.5429 = 54.29 cM Incorrect distance =

½(96) + 3×(0)

5,600

48 + 0

5,600

= 0.0086 = 0.86 cM Incorrect distance =

½(2,352) + 3×(0)

5,600

1,176 + 0

5,600

1,176

5,600

= 0.2100 = 21 cM Incorrect MC

063f_8e71

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene J is correlated with the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.
Gene W is linked with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

2,045

1,864

TOTAL =

4,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes J and W

distance =

½(1,864) + 3×(91)

4,000

932 + 273

4,000

1,205

4,000

= 0.3013 = 30.12 cM Correct distance =

½(2,045) + 3×(0)

4,000

1022.5 + 0

4,000

1022.5

4,000

= 0.2556 = 25.56 cM Incorrect distance =

½(91) + 3×(91)

4,000

45.5 + 273

4,000

318.5

4,000

= 0.0796 = 7.96 cM Incorrect distance =

½(1,864) + 3×(0)

4,000

932 + 0

4,000

932

4,000

= 0.2330 = 23.30 cM Incorrect distance =

½(2,045) + 3×(91)

4,000

1022.5 + 273

4,000

1295.5

4,000

= 0.3239 = 32.39 cM Incorrect distance =

½(1,864 + 2,045) + 3×(91)

4,000

1954.5 + 273

4,000

2227.5

4,000

= 0.5569 = 55.69 cM Incorrect MC

7427_8cf9

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene N is affiliated with the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.
Gene P is analogous to the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

171

4,048

5,181

TOTAL =

9,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes N and P

distance =

½(171) + 3×(171)

9,400

85.5 + 513

9,400

598.5

9,400

= 0.0637 = 6.37 cM Incorrect distance =

½(171) + 3×(0)

9,400

85.5 + 0

9,400

85.5

9,400

= 0.0091 = 0.91 cM Incorrect distance =

½(4,048) + 3×(0)

9,400

2,024 + 0

9,400

2,024

9,400

= 0.2153 = 21.53 cM Incorrect distance =

½(4,048 + 5,181) + 3×(171)

9,400

4614.5 + 513

9,400

5127.5

9,400

= 0.5455 = 54.55 cM Incorrect distance =

½(4,048) + 3×(171)

9,400

2,024 + 513

9,400

2,537

9,400

= 0.2699 = 26.99 cM Correct distance =

½(0) + 3×(171)

9,400

0 + 513

9,400

513

9,400

= 0.0546 = 5.46 cM Incorrect MC

4056_29b7

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is related to the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene M is linked with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

4,716

3,354

130

TOTAL =

8,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and M

distance =

½(4,716) + 3×(130)

8,200

2,358 + 390

8,200

2,748

8,200

= 0.3351 = 33.51 cM Incorrect distance =

½(4,716) + 3×(0)

8,200

2,358 + 0

8,200

2,358

8,200

= 0.2876 = 28.76 cM Incorrect distance =

½(3,354 + 4,716) + 3×(130)

8,200

4,035 + 390

8,200

4,425

8,200

= 0.5396 = 53.96 cM Incorrect distance =

½(130) + 3×(0)

8,200

65 + 0

8,200

= 0.0079 = 0.79 cM Incorrect distance =

½(3,354) + 3×(130)

8,200

1,677 + 390

8,200

2,067

8,200

= 0.2521 = 25.21 cM Correct distance =

½(130) + 3×(130)

8,200

65 + 390

8,200

455

8,200

= 0.0555 = 5.55 cM Incorrect MC

6e22_36ae

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene W is linked with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.
Gene X is linked with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

1,554

1,773

TOTAL =

3,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes W and X

distance =

½(73) + 3×(73)

3,400

36.5 + 219

3,400

255.5

3,400

= 0.0751 = 7.51 cM Incorrect distance =

½(0) + 3×(73)

3,400

0 + 219

3,400

219

3,400

= 0.0644 = 6.44 cM Incorrect distance =

½(1,554) + 3×(73)

3,400

777 + 219

3,400

996

3,400

= 0.2929 = 29.29 cM Correct distance =

½(73) + 3×(0)

3,400

36.5 + 0

3,400

36.5

3,400

= 0.0107 = 1.07 cM Incorrect distance =

½(1,773) + 3×(73)

3,400

886.5 + 219

3,400

1105.5

3,400

= 0.3251 = 32.51 cM Incorrect distance =

½(1,554) + 3×(0)

3,400

777 + 0

3,400

777

3,400

= 0.2285 = 22.85 cM Incorrect MC

7f19_0850

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is linked with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene R is connected with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

1,508

1,826

TOTAL =

3,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and R

distance =

½(66) + 3×(66)

3,400

33 + 198

3,400

231

3,400

= 0.0679 = 6.79 cM Incorrect distance =

½(1,508) + 3×(66)

3,400

754 + 198

3,400

952

3,400

= 0.2800 = 28 cM Correct distance =

½(1,826) + 3×(0)

3,400

913 + 0

3,400

913

3,400

= 0.2685 = 26.85 cM Incorrect distance =

½(1,508 + 1,826) + 3×(66)

3,400

1,667 + 198

3,400

1,865

3,400

= 0.5485 = 54.85 cM Incorrect distance =

½(1,508) + 3×(0)

3,400

754 + 0

3,400

754

3,400

= 0.2218 = 22.18 cM Incorrect distance =

½(0) + 3×(66)

3,400

0 + 198

3,400

198

3,400

= 0.0582 = 5.82 cM Incorrect MC

a85e_36ff

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is affiliated with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene T is associated with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

162

3,974

5,264

TOTAL =

9,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and T

distance =

½(3,974) + 3×(0)

9,400

1,987 + 0

9,400

1,987

9,400

= 0.2114 = 21.14 cM Incorrect distance =

½(3,974 + 5,264) + 3×(162)

9,400

4,619 + 486

9,400

5,105

9,400

= 0.5431 = 54.31 cM Incorrect distance =

½(162) + 3×(0)

9,400

81 + 0

9,400

= 0.0086 = 0.86 cM Incorrect distance =

½(3,974) + 3×(162)

9,400

1,987 + 486

9,400

2,473

9,400

= 0.2631 = 26.31 cM Correct distance =

½(162) + 3×(162)

9,400

81 + 486

9,400

567

9,400

= 0.0603 = 6.03 cM Incorrect distance =

½(5,264) + 3×(0)

9,400

2,632 + 0

9,400

2,632

9,400

= 0.2800 = 28 cM Incorrect MC

bf3b_3fe0

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is affiliated with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene R is correlated with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

1,472

1,270

TOTAL =

2,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and R

distance =

½(58) + 3×(0)

2,800

29 + 0

2,800

= 0.0104 = 1.04 cM Incorrect distance =

½(1,270) + 3×(58)

2,800

635 + 174

2,800

809

2,800

= 0.2889 = 28.89 cM Correct distance =

½(1,270) + 3×(0)

2,800

635 + 0

2,800

635

2,800

= 0.2268 = 22.68 cM Incorrect distance =

½(1,270 + 1,472) + 3×(58)

2,800

1,371 + 174

2,800

1,545

2,800

= 0.5518 = 55.18 cM Incorrect distance =

½(58) + 3×(58)

2,800

29 + 174

2,800

203

2,800

= 0.0725 = 7.25 cM Incorrect distance =

½(0) + 3×(58)

2,800

0 + 174

2,800

174

2,800

= 0.0621 = 6.21 cM Incorrect MC

ef93_a5ca

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is affiliated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene N is connected with the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

1,865

1,472

TOTAL =

3,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and N

distance =

½(1,472) + 3×(63)

3,400

736 + 189

3,400

925

3,400

= 0.2721 = 27.21 cM Correct distance =

½(1,865) + 3×(63)

3,400

932.5 + 189

3,400

1121.5

3,400

= 0.3299 = 32.99 cM Incorrect distance =

½(1,472 + 1,865) + 3×(63)

3,400

1668.5 + 189

3,400

1857.5

3,400

= 0.5463 = 54.63 cM Incorrect distance =

½(63) + 3×(63)

3,400

31.5 + 189

3,400

220.5

3,400

= 0.0649 = 6.49 cM Incorrect distance =

½(1,472) + 3×(0)

3,400

736 + 0

3,400

736

3,400

= 0.2165 = 21.65 cM Incorrect distance =

½(1,865) + 3×(0)

3,400

932.5 + 0

3,400

932.5

3,400

= 0.2743 = 27.43 cM Incorrect MC

5da7_4ceb

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene T is correlated with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.
Gene Y is connected with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

3,474

2,432

TOTAL =

6,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes T and Y

distance =

½(0) + 3×(94)

6,000

0 + 282

6,000

282

6,000

= 0.0470 = 4.70 cM Incorrect distance =

½(94) + 3×(94)

6,000

47 + 282

6,000

329

6,000

= 0.0548 = 5.48 cM Incorrect distance =

½(3,474) + 3×(94)

6,000

1,737 + 282

6,000

2,019

6,000

= 0.3365 = 33.65 cM Incorrect distance =

½(3,474) + 3×(0)

6,000

1,737 + 0

6,000

1,737

6,000

= 0.2895 = 28.95 cM Incorrect distance =

½(2,432) + 3×(0)

6,000

1,216 + 0

6,000

1,216

6,000

= 0.2027 = 20.27 cM Incorrect distance =

½(2,432) + 3×(94)

6,000

1,216 + 282

6,000

1,498

6,000

= 0.2497 = 24.97 cM Correct MC

50e2_7eda

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene X is analogous to the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.
Gene Y is associated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

2,529

2,354

117

TOTAL =

5,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes X and Y

distance =

½(2,529) + 3×(117)

5,000

1264.5 + 351

5,000

1615.5

5,000

= 0.3231 = 32.31 cM Incorrect distance =

½(117) + 3×(0)

5,000

58.5 + 0

5,000

58.5

5,000

= 0.0117 = 1.17 cM Incorrect distance =

½(2,354) + 3×(0)

5,000

1,177 + 0

5,000

1,177

5,000

= 0.2354 = 23.54 cM Incorrect distance =

½(0) + 3×(117)

5,000

0 + 351

5,000

351

5,000

= 0.0702 = 7.02 cM Incorrect distance =

½(2,354 + 2,529) + 3×(117)

5,000

2441.5 + 351

5,000

2792.5

5,000

= 0.5585 = 55.85 cM Incorrect distance =

½(2,354) + 3×(117)

5,000

1,177 + 351

5,000

1,528

5,000

= 0.3056 = 30.56 cM Correct MC

d45a_9f94

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is related to the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene M is connected with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

1,914

1,242

TOTAL =

3,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and M

distance =

½(1,914) + 3×(0)

3,200

957 + 0

3,200

957

3,200

= 0.2991 = 29.91 cM Incorrect distance =

½(44) + 3×(0)

3,200

22 + 0

3,200

= 0.0069 = 0.69 cM Incorrect distance =

½(1,242) + 3×(44)

3,200

621 + 132

3,200

753

3,200

= 0.2353 = 23.53 cM Correct distance =

½(1,914) + 3×(44)

3,200

957 + 132

3,200

1,089

3,200

= 0.3403 = 34.03 cM Incorrect distance =

½(0) + 3×(44)

3,200

0 + 132

3,200

132

3,200

= 0.0413 = 4.12 cM Incorrect distance =

½(1,242 + 1,914) + 3×(44)

3,200

1,578 + 132

3,200

1,710

3,200

= 0.5344 = 53.44 cM Incorrect MC

4175_7e02

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene M is connected with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.
Gene Y is affiliated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

150

3,256

3,794

TOTAL =

7,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes M and Y

distance =

½(3,256) + 3×(150)

7,200

1,628 + 450

7,200

2,078

7,200

= 0.2886 = 28.86 cM Correct distance =

½(3,794) + 3×(0)

7,200

1,897 + 0

7,200

1,897

7,200

= 0.2635 = 26.35 cM Incorrect distance =

½(3,256) + 3×(0)

7,200

1,628 + 0

7,200

1,628

7,200

= 0.2261 = 22.61 cM Incorrect distance =

½(3,794) + 3×(150)

7,200

1,897 + 450

7,200

2,347

7,200

= 0.3260 = 32.60 cM Incorrect distance =

½(150) + 3×(150)

7,200

75 + 450

7,200

525

7,200

= 0.0729 = 7.29 cM Incorrect distance =

½(150) + 3×(0)

7,200

75 + 0

7,200

= 0.0104 = 1.04 cM Incorrect MC

e0aa_d55a

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is related to the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene H is correlated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

154

3,046

3,200

TOTAL =

6,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and H

distance =

½(0) + 3×(154)

6,400

0 + 462

6,400

462

6,400

= 0.0722 = 7.22 cM Incorrect distance =

½(3,046) + 3×(0)

6,400

1,523 + 0

6,400

1,523

6,400

= 0.2380 = 23.80 cM Incorrect distance =

½(3,200) + 3×(0)

6,400

1,600 + 0

6,400

1,600

6,400

= 0.2500 = 25 cM Incorrect distance =

½(154) + 3×(0)

6,400

77 + 0

6,400

= 0.0120 = 1.20 cM Incorrect distance =

½(3,046) + 3×(154)

6,400

1,523 + 462

6,400

1,985

6,400

= 0.3102 = 31.02 cM Correct distance =

½(154) + 3×(154)

6,400

77 + 462

6,400

539

6,400

= 0.0842 = 8.42 cM Incorrect MC

2081_1b57

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is correlated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene K is affiliated with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.

Set #

Tetrad Genotypes

Progeny
Count

1,098

1,662

TOTAL =

2,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and K

distance =

½(1,098) + 3×(40)

2,800

549 + 120

2,800

669

2,800

= 0.2389 = 23.89 cM Correct distance =

½(40) + 3×(40)

2,800

20 + 120

2,800

140

2,800

= 0.0500 = 5 cM Incorrect distance =

½(0) + 3×(40)

2,800

0 + 120

2,800

120

2,800

= 0.0429 = 4.29 cM Incorrect distance =

½(1,662) + 3×(40)

2,800

831 + 120

2,800

951

2,800

= 0.3396 = 33.96 cM Incorrect distance =

½(1,098) + 3×(0)

2,800

549 + 0

2,800

549

2,800

= 0.1961 = 19.61 cM Incorrect distance =

½(40) + 3×(0)

2,800

20 + 0

2,800

= 0.0071 = 0.71 cM Incorrect MC

b734_0006

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is affiliated with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene N is correlated with the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

118

2,820

3,662

TOTAL =

6,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and N

distance =

½(0) + 3×(118)

6,600

0 + 354

6,600

354

6,600

= 0.0536 = 5.36 cM Incorrect distance =

½(118) + 3×(0)

6,600

59 + 0

6,600

= 0.0089 = 0.89 cM Incorrect distance =

½(2,820) + 3×(118)

6,600

1,410 + 354

6,600

1,764

6,600

= 0.2673 = 26.73 cM Correct distance =

½(2,820) + 3×(0)

6,600

1,410 + 0

6,600

1,410

6,600

= 0.2136 = 21.36 cM Incorrect distance =

½(2,820 + 3,662) + 3×(118)

6,600

3,241 + 354

6,600

3,595

6,600

= 0.5447 = 54.47 cM Incorrect distance =

½(3,662) + 3×(0)

6,600

1,831 + 0

6,600

1,831

6,600

= 0.2774 = 27.74 cM Incorrect MC

85f8_2799

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is analogous to the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene P is related to the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

157

3,966

5,477

TOTAL =

9,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and P

distance =

½(5,477) + 3×(157)

9,600

2738.5 + 471

9,600

3209.5

9,600

= 0.3343 = 33.43 cM Incorrect distance =

½(157) + 3×(0)

9,600

78.5 + 0

9,600

78.5

9,600

= 0.0082 = 0.82 cM Incorrect distance =

½(3,966) + 3×(0)

9,600

1,983 + 0

9,600

1,983

9,600

= 0.2066 = 20.66 cM Incorrect distance =

½(3,966 + 5,477) + 3×(157)

9,600

4721.5 + 471

9,600

5192.5

9,600

= 0.5409 = 54.09 cM Incorrect distance =

½(0) + 3×(157)

9,600

0 + 471

9,600

471

9,600

= 0.0491 = 4.91 cM Incorrect distance =

½(3,966) + 3×(157)

9,600

1,983 + 471

9,600

2,454

9,600

= 0.2556 = 25.56 cM Correct MC

7e18_ab50

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is analogous to the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene X is analogous to the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

2,710

4,398

TOTAL =

7,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and X

distance =

½(4,398) + 3×(0)

7,200

2,199 + 0

7,200

2,199

7,200

= 0.3054 = 30.54 cM Incorrect distance =

½(2,710) + 3×(92)

7,200

1,355 + 276

7,200

1,631

7,200

= 0.2265 = 22.65 cM Correct distance =

½(0) + 3×(92)

7,200

0 + 276

7,200

276

7,200

= 0.0383 = 3.83 cM Incorrect distance =

½(2,710) + 3×(0)

7,200

1,355 + 0

7,200

1,355

7,200

= 0.1882 = 18.82 cM Incorrect distance =

½(4,398) + 3×(92)

7,200

2,199 + 276

7,200

2,475

7,200

= 0.3438 = 34.38 cM Incorrect distance =

½(92) + 3×(0)

7,200

46 + 0

7,200

= 0.0064 = 0.64 cM Incorrect MC

29ad_b39e

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is correlated with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene W is associated with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

1,198

774

TOTAL =

2,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and W

distance =

½(774 + 1,198) + 3×(28)

2,000

986 + 84

2,000

1,070

2,000

= 0.5350 = 53.50 cM Incorrect distance =

½(1,198) + 3×(28)

2,000

599 + 84

2,000

683

2,000

= 0.3415 = 34.15 cM Incorrect distance =

½(28) + 3×(0)

2,000

14 + 0

2,000

= 0.0070 = 0.70 cM Incorrect distance =

½(28) + 3×(28)

2,000

14 + 84

2,000

= 0.0490 = 4.90 cM Incorrect distance =

½(0) + 3×(28)

2,000

0 + 84

2,000

= 0.0420 = 4.20 cM Incorrect distance =

½(774) + 3×(28)

2,000

387 + 84

2,000

471

2,000

= 0.2355 = 23.55 cM Correct MC

3602_0735

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is affiliated with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene T is affiliated with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

106

3,042

4,852

TOTAL =

8,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and T

distance =

½(3,042) + 3×(106)

8,000

1,521 + 318

8,000

1,839

8,000

= 0.2299 = 22.99 cM Correct distance =

½(3,042 + 4,852) + 3×(106)

8,000

3,947 + 318

8,000

4,265

8,000

= 0.5331 = 53.31 cM Incorrect distance =

½(0) + 3×(106)

8,000

0 + 318

8,000

318

8,000

= 0.0398 = 3.98 cM Incorrect distance =

½(106) + 3×(0)

8,000

53 + 0

8,000

= 0.0066 = 0.66 cM Incorrect distance =

½(4,852) + 3×(106)

8,000

2,426 + 318

8,000

2,744

8,000

= 0.3430 = 34.30 cM Incorrect distance =

½(3,042) + 3×(0)

8,000

1,521 + 0

8,000

1,521

8,000

= 0.1901 = 19.01 cM Incorrect MC

c8f1_6eec

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is correlated with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene H is associated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

1,289

690

TOTAL =

2,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and H

distance =

½(0) + 3×(21)

2,000

0 + 63

2,000

= 0.0315 = 3.15 cM Incorrect distance =

½(21) + 3×(0)

2,000

10.5 + 0

2,000

10.5

2,000

= 0.0053 = 0.53 cM Incorrect distance =

½(1,289) + 3×(0)

2,000

644.5 + 0

2,000

644.5

2,000

= 0.3222 = 32.23 cM Incorrect distance =

½(690) + 3×(21)

2,000

345 + 63

2,000

408

2,000

= 0.2040 = 20.40 cM Correct distance =

½(1,289) + 3×(21)

2,000

644.5 + 63

2,000

707.5

2,000

= 0.3538 = 35.38 cM Incorrect distance =

½(690 + 1,289) + 3×(21)

2,000

989.5 + 63

2,000

1052.5

2,000

= 0.5262 = 52.62 cM Incorrect MC

cf2b_4ae0

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is associated with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene T is related to the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

704

866

TOTAL =

1,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and T

distance =

½(30) + 3×(30)

1,600

15 + 90

1,600

105

1,600

= 0.0656 = 6.56 cM Incorrect distance =

½(866) + 3×(30)

1,600

433 + 90

1,600

523

1,600

= 0.3269 = 32.69 cM Incorrect distance =

½(704) + 3×(30)

1,600

352 + 90

1,600

442

1,600

= 0.2762 = 27.62 cM Correct distance =

½(704 + 866) + 3×(30)

1,600

785 + 90

1,600

875

1,600

= 0.5469 = 54.69 cM Incorrect distance =

½(866) + 3×(0)

1,600

433 + 0

1,600

433

1,600

= 0.2706 = 27.06 cM Incorrect distance =

½(30) + 3×(0)

1,600

15 + 0

1,600

= 0.0094 = 0.94 cM Incorrect MC

dd53_a77d

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is related to the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene J is related to the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.

Set #

Tetrad Genotypes

Progeny
Count

117

2,964

4,119

TOTAL =

7,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and J

distance =

½(4,119) + 3×(117)

7,200

2059.5 + 351

7,200

2410.5

7,200

= 0.3348 = 33.48 cM Incorrect distance =

½(0) + 3×(117)

7,200

0 + 351

7,200

351

7,200

= 0.0488 = 4.88 cM Incorrect distance =

½(2,964) + 3×(117)

7,200

1,482 + 351

7,200

1,833

7,200

= 0.2546 = 25.46 cM Correct distance =

½(2,964 + 4,119) + 3×(117)

7,200

3541.5 + 351

7,200

3892.5

7,200

= 0.5406 = 54.06 cM Incorrect distance =

½(4,119) + 3×(0)

7,200

2059.5 + 0

7,200

2059.5

7,200

= 0.2860 = 28.60 cM Incorrect distance =

½(2,964) + 3×(0)

7,200

1,482 + 0

7,200

1,482

7,200

= 0.2058 = 20.58 cM Incorrect MC

e9d6_be3b

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is linked with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene N is associated with the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

1,775

994

TOTAL =

2,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and N

distance =

½(994 + 1,775) + 3×(31)

2,800

1384.5 + 93

2,800

1477.5

2,800

= 0.5277 = 52.77 cM Incorrect distance =

½(994) + 3×(31)

2,800

497 + 93

2,800

590

2,800

= 0.2107 = 21.07 cM Correct distance =

½(1,775) + 3×(0)

2,800

887.5 + 0

2,800

887.5

2,800

= 0.3170 = 31.70 cM Incorrect distance =

½(994) + 3×(0)

2,800

497 + 0

2,800

497

2,800

= 0.1775 = 17.75 cM Incorrect distance =

½(0) + 3×(31)

2,800

0 + 93

2,800

= 0.0332 = 3.32 cM Incorrect distance =

½(31) + 3×(31)

2,800

15.5 + 93

2,800

108.5

2,800

= 0.0387 = 3.88 cM Incorrect MC

fbf6_d940

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is analogous to the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene M is associated with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

2,806

2,478

116

TOTAL =

5,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and M

distance =

½(116) + 3×(0)

5,400

58 + 0

5,400

= 0.0107 = 1.07 cM Incorrect distance =

½(2,478) + 3×(0)

5,400

1,239 + 0

5,400

1,239

5,400

= 0.2294 = 22.94 cM Incorrect distance =

½(2,478 + 2,806) + 3×(116)

5,400

2,642 + 348

5,400

2,990

5,400

= 0.5537 = 55.37 cM Incorrect distance =

½(0) + 3×(116)

5,400

0 + 348

5,400

348

5,400

= 0.0644 = 6.44 cM Incorrect distance =

½(2,478) + 3×(116)

5,400

1,239 + 348

5,400

1,587

5,400

= 0.2939 = 29.39 cM Correct distance =

½(116) + 3×(116)

5,400

58 + 348

5,400

406

5,400

= 0.0752 = 7.52 cM Incorrect MC

a7f2_3ad0

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is linked with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene W is connected with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

5,533

3,916

151

TOTAL =

9,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and W

distance =

½(151) + 3×(0)

9,600

75.5 + 0

9,600

75.5

9,600

= 0.0079 = 0.79 cM Incorrect distance =

½(0) + 3×(151)

9,600

0 + 453

9,600

453

9,600

= 0.0472 = 4.72 cM Incorrect distance =

½(5,533) + 3×(151)

9,600

2766.5 + 453

9,600

3219.5

9,600

= 0.3354 = 33.54 cM Incorrect distance =

½(3,916 + 5,533) + 3×(151)

9,600

4724.5 + 453

9,600

5177.5

9,600

= 0.5393 = 53.93 cM Incorrect distance =

½(3,916) + 3×(151)

9,600

1,958 + 453

9,600

2,411

9,600

= 0.2511 = 25.11 cM Correct distance =

½(151) + 3×(151)

9,600

75.5 + 453

9,600

528.5

9,600

= 0.0551 = 5.51 cM Incorrect MC

7cf2_5341

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene R is connected with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.
Gene X is linked with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

1,768

1,946

TOTAL =

3,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes R and X

distance =

½(0) + 3×(86)

3,800

0 + 258

3,800

258

3,800

= 0.0679 = 6.79 cM Incorrect distance =

½(1,768 + 1,946) + 3×(86)

3,800

1,857 + 258

3,800

2,115

3,800

= 0.5566 = 55.66 cM Incorrect distance =

½(1,768) + 3×(86)

3,800

884 + 258

3,800

1,142

3,800

= 0.3005 = 30.05 cM Correct distance =

½(86) + 3×(86)

3,800

43 + 258

3,800

301

3,800

= 0.0792 = 7.92 cM Incorrect distance =

½(1,768) + 3×(0)

3,800

884 + 0

3,800

884

3,800

= 0.2326 = 23.26 cM Incorrect distance =

½(1,946) + 3×(0)

3,800

973 + 0

3,800

973

3,800

= 0.2561 = 25.61 cM Incorrect MC

53eb_8e20

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is correlated with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene R is analogous to the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

1,004

1,355

TOTAL =

2,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and R

distance =

½(41) + 3×(41)

2,400

20.5 + 123

2,400

143.5

2,400

= 0.0598 = 5.98 cM Incorrect distance =

½(1,004) + 3×(41)

2,400

502 + 123

2,400

625

2,400

= 0.2604 = 26.04 cM Correct distance =

½(0) + 3×(41)

2,400

0 + 123

2,400

123

2,400

= 0.0512 = 5.12 cM Incorrect distance =

½(1,355) + 3×(41)

2,400

677.5 + 123

2,400

800.5

2,400

= 0.3335 = 33.35 cM Incorrect distance =

½(41) + 3×(0)

2,400

20.5 + 0

2,400

20.5

2,400

= 0.0085 = 0.85 cM Incorrect distance =

½(1,004) + 3×(0)

2,400

502 + 0

2,400

502

2,400

= 0.2092 = 20.92 cM Incorrect MC

59e3_4062

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is correlated with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene T is connected with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

1,129

1,022

TOTAL =

2,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and T

distance =

½(1,022) + 3×(0)

2,200

511 + 0

2,200

511

2,200

= 0.2323 = 23.23 cM Incorrect distance =

½(1,022 + 1,129) + 3×(49)

2,200

1075.5 + 147

2,200

1222.5

2,200

= 0.5557 = 55.57 cM Incorrect distance =

½(49) + 3×(49)

2,200

24.5 + 147

2,200

171.5

2,200

= 0.0780 = 7.80 cM Incorrect distance =

½(1,022) + 3×(49)

2,200

511 + 147

2,200

658

2,200

= 0.2991 = 29.91 cM Correct distance =

½(1,129) + 3×(49)

2,200

564.5 + 147

2,200

711.5

2,200

= 0.3234 = 32.34 cM Incorrect distance =

½(1,129) + 3×(0)

2,200

564.5 + 0

2,200

564.5

2,200

= 0.2566 = 25.66 cM Incorrect MC

c0f1_1621

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene J is linked with the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.
Gene M is connected with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

4,614

4,550

236

TOTAL =

9,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes J and M

distance =

½(4,614) + 3×(0)

9,400

2,307 + 0

9,400

2,307

9,400

= 0.2454 = 24.54 cM Incorrect distance =

½(4,550 + 4,614) + 3×(236)

9,400

4,582 + 708

9,400

5,290

9,400

= 0.5628 = 56.28 cM Incorrect distance =

½(236) + 3×(236)

9,400

118 + 708

9,400

826

9,400

= 0.0879 = 8.79 cM Incorrect distance =

½(236) + 3×(0)

9,400

118 + 0

9,400

118

9,400

= 0.0126 = 1.26 cM Incorrect distance =

½(4,550) + 3×(236)

9,400

2,275 + 708

9,400

2,983

9,400

= 0.3173 = 31.73 cM Correct distance =

½(0) + 3×(236)

9,400

0 + 708

9,400

708

9,400

= 0.0753 = 7.53 cM Incorrect MC

a412_7e7d

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene J is connected with the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.
Gene R is analogous to the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

3,528

2,756

116

TOTAL =

6,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes J and R

distance =

½(116) + 3×(116)

6,400

58 + 348

6,400

406

6,400

= 0.0634 = 6.34 cM Incorrect distance =

½(0) + 3×(116)

6,400

0 + 348

6,400

348

6,400

= 0.0544 = 5.44 cM Incorrect distance =

½(2,756) + 3×(0)

6,400

1,378 + 0

6,400

1,378

6,400

= 0.2153 = 21.53 cM Incorrect distance =

½(3,528) + 3×(0)

6,400

1,764 + 0

6,400

1,764

6,400

= 0.2756 = 27.56 cM Incorrect distance =

½(3,528) + 3×(116)

6,400

1,764 + 348

6,400

2,112

6,400

= 0.3300 = 33 cM Incorrect distance =

½(2,756) + 3×(116)

6,400

1,378 + 348

6,400

1,726

6,400

= 0.2697 = 26.97 cM Correct MC

d63b_b652

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is correlated with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene M is associated with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

3,395

3,058

147

TOTAL =

6,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and M

distance =

½(3,395) + 3×(147)

6,600

1697.5 + 441

6,600

2138.5

6,600

= 0.3240 = 32.40 cM Incorrect distance =

½(147) + 3×(147)

6,600

73.5 + 441

6,600

514.5

6,600

= 0.0780 = 7.80 cM Incorrect distance =

½(3,058) + 3×(147)

6,600

1,529 + 441

6,600

1,970

6,600

= 0.2985 = 29.85 cM Correct distance =

½(147) + 3×(0)

6,600

73.5 + 0

6,600

73.5

6,600

= 0.0111 = 1.11 cM Incorrect distance =

½(3,058) + 3×(0)

6,600

1,529 + 0

6,600

1,529

6,600

= 0.2317 = 23.17 cM Incorrect distance =

½(3,058 + 3,395) + 3×(147)

6,600

3226.5 + 441

6,600

3667.5

6,600

= 0.5557 = 55.57 cM Incorrect MC

62e9_7912

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is analogous to the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene M is associated with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

3,680

2,618

102

TOTAL =

6,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and M

distance =

½(102) + 3×(102)

6,400

51 + 306

6,400

357

6,400

= 0.0558 = 5.58 cM Incorrect distance =

½(2,618) + 3×(0)

6,400

1,309 + 0

6,400

1,309

6,400

= 0.2045 = 20.45 cM Incorrect distance =

½(3,680) + 3×(0)

6,400

1,840 + 0

6,400

1,840

6,400

= 0.2875 = 28.75 cM Incorrect distance =

½(2,618 + 3,680) + 3×(102)

6,400

3,149 + 306

6,400

3,455

6,400

= 0.5398 = 53.98 cM Incorrect distance =

½(2,618) + 3×(102)

6,400

1,309 + 306

6,400

1,615

6,400

= 0.2523 = 25.23 cM Correct distance =

½(0) + 3×(102)

6,400

0 + 306

6,400

306

6,400

= 0.0478 = 4.78 cM Incorrect MC

c29f_0ea8

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene W is linked with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.
Gene Y is linked with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

212

4,372

4,816

TOTAL =

9,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes W and Y

distance =

½(212) + 3×(212)

9,400

106 + 636

9,400

742

9,400

= 0.0789 = 7.89 cM Incorrect distance =

½(4,816) + 3×(212)

9,400

2,408 + 636

9,400

3,044

9,400

= 0.3238 = 32.38 cM Incorrect distance =

½(4,372) + 3×(212)

9,400

2,186 + 636

9,400

2,822

9,400

= 0.3002 = 30.02 cM Correct distance =

½(0) + 3×(212)

9,400

0 + 636

9,400

636

9,400

= 0.0677 = 6.77 cM Incorrect distance =

½(4,372) + 3×(0)

9,400

2,186 + 0

9,400

2,186

9,400

= 0.2326 = 23.26 cM Incorrect distance =

½(4,372 + 4,816) + 3×(212)

9,400

4,594 + 636

9,400

5,230

9,400

= 0.5564 = 55.64 cM Incorrect MC

6fb1_33de

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is linked with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene R is linked with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

2,570

2,502

128

TOTAL =

5,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and R

distance =

½(2,502) + 3×(128)

5,200

1,251 + 384

5,200

1,635

5,200

= 0.3144 = 31.44 cM Correct distance =

½(2,502) + 3×(0)

5,200

1,251 + 0

5,200

1,251

5,200

= 0.2406 = 24.06 cM Incorrect distance =

½(2,570) + 3×(128)

5,200

1,285 + 384

5,200

1,669

5,200

= 0.3210 = 32.10 cM Incorrect distance =

½(2,502 + 2,570) + 3×(128)

5,200

2,536 + 384

5,200

2,920

5,200

= 0.5615 = 56.15 cM Incorrect distance =

½(2,570) + 3×(0)

5,200

1,285 + 0

5,200

1,285

5,200

= 0.2471 = 24.71 cM Incorrect distance =

½(128) + 3×(0)

5,200

64 + 0

5,200

= 0.0123 = 1.23 cM Incorrect MC

d3d1_fb62

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is correlated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene K is associated with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.

Set #

Tetrad Genotypes

Progeny
Count

2,838

5,073

TOTAL =

8,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and K

distance =

½(89) + 3×(89)

8,000

44.5 + 267

8,000

311.5

8,000

= 0.0389 = 3.89 cM Incorrect distance =

½(2,838 + 5,073) + 3×(89)

8,000

3955.5 + 267

8,000

4222.5

8,000

= 0.5278 = 52.78 cM Incorrect distance =

½(2,838) + 3×(0)

8,000

1,419 + 0

8,000

1,419

8,000

= 0.1774 = 17.74 cM Incorrect distance =

½(2,838) + 3×(89)

8,000

1,419 + 267

8,000

1,686

8,000

= 0.2107 = 21.07 cM Correct distance =

½(5,073) + 3×(89)

8,000

2536.5 + 267

8,000

2803.5

8,000

= 0.3504 = 35.04 cM Incorrect distance =

½(5,073) + 3×(0)

8,000

2536.5 + 0

8,000

2536.5

8,000

= 0.3171 = 31.71 cM Incorrect MC

6596_a0e4

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is affiliated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene X is related to the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

770

1,202

TOTAL =

2,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and X

distance =

½(770 + 1,202) + 3×(28)

2,000

986 + 84

2,000

1,070

2,000

= 0.5350 = 53.50 cM Incorrect distance =

½(1,202) + 3×(28)

2,000

601 + 84

2,000

685

2,000

= 0.3425 = 34.25 cM Incorrect distance =

½(0) + 3×(28)

2,000

0 + 84

2,000

= 0.0420 = 4.20 cM Incorrect distance =

½(1,202) + 3×(0)

2,000

601 + 0

2,000

601

2,000

= 0.3005 = 30.05 cM Incorrect distance =

½(770) + 3×(28)

2,000

385 + 84

2,000

469

2,000

= 0.2345 = 23.45 cM Correct distance =

½(28) + 3×(28)

2,000

14 + 84

2,000

= 0.0490 = 4.90 cM Incorrect MC

92d7_c1e3

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is correlated with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene Y is related to the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

1,512

2,027

TOTAL =

3,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and Y

distance =

½(61) + 3×(61)

3,600

30.5 + 183

3,600

213.5

3,600

= 0.0593 = 5.93 cM Incorrect distance =

½(1,512) + 3×(61)

3,600

756 + 183

3,600

939

3,600

= 0.2608 = 26.08 cM Correct distance =

½(1,512 + 2,027) + 3×(61)

3,600

1769.5 + 183

3,600

1952.5

3,600

= 0.5424 = 54.24 cM Incorrect distance =

½(0) + 3×(61)

3,600

0 + 183

3,600

183

3,600

= 0.0508 = 5.08 cM Incorrect distance =

½(1,512) + 3×(0)

3,600

756 + 0

3,600

756

3,600

= 0.2100 = 21 cM Incorrect distance =

½(2,027) + 3×(61)

3,600

1013.5 + 183

3,600

1196.5

3,600

= 0.3324 = 33.24 cM Incorrect MC

4df5_5940

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is connected with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene Y is linked with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

2,100

3,429

TOTAL =

5,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and Y

distance =

½(2,100 + 3,429) + 3×(71)

5,600

2764.5 + 213

5,600

2977.5

5,600

= 0.5317 = 53.17 cM Incorrect distance =

½(71) + 3×(71)

5,600

35.5 + 213

5,600

248.5

5,600

= 0.0444 = 4.44 cM Incorrect distance =

½(2,100) + 3×(71)

5,600

1,050 + 213

5,600

1,263

5,600

= 0.2255 = 22.55 cM Correct distance =

½(3,429) + 3×(71)

5,600

1714.5 + 213

5,600

1927.5

5,600

= 0.3442 = 34.42 cM Incorrect distance =

½(2,100) + 3×(0)

5,600

1,050 + 0

5,600

1,050

5,600

= 0.1875 = 18.75 cM Incorrect distance =

½(0) + 3×(71)

5,600

0 + 213

5,600

213

5,600

= 0.0380 = 3.80 cM Incorrect MC

6b98_b09e

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is associated with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene Y is related to the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

2,440

3,261

TOTAL =

5,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and Y

distance =

½(99) + 3×(0)

5,800

49.5 + 0

5,800

49.5

5,800

= 0.0085 = 0.85 cM Incorrect distance =

½(0) + 3×(99)

5,800

0 + 297

5,800

297

5,800

= 0.0512 = 5.12 cM Incorrect distance =

½(99) + 3×(99)

5,800

49.5 + 297

5,800

346.5

5,800

= 0.0597 = 5.97 cM Incorrect distance =

½(2,440) + 3×(0)

5,800

1,220 + 0

5,800

1,220

5,800

= 0.2103 = 21.03 cM Incorrect distance =

½(2,440) + 3×(99)

5,800

1,220 + 297

5,800

1,517

5,800

= 0.2616 = 26.16 cM Correct distance =

½(3,261) + 3×(0)

5,800

1630.5 + 0

5,800

1630.5

5,800

= 0.2811 = 28.11 cM Incorrect MC

a640_6b0f

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is associated with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene K is related to the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.

Set #

Tetrad Genotypes

Progeny
Count

4,652

4,516

232

TOTAL =

9,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and K

distance =

½(4,516) + 3×(0)

9,400

2,258 + 0

9,400

2,258

9,400

= 0.2402 = 24.02 cM Incorrect distance =

½(232) + 3×(232)

9,400

116 + 696

9,400

812

9,400

= 0.0864 = 8.64 cM Incorrect distance =

½(4,516) + 3×(232)

9,400

2,258 + 696

9,400

2,954

9,400

= 0.3143 = 31.43 cM Correct distance =

½(0) + 3×(232)

9,400

0 + 696

9,400

696

9,400

= 0.0740 = 7.40 cM Incorrect distance =

½(4,652) + 3×(0)

9,400

2,326 + 0

9,400

2,326

9,400

= 0.2474 = 24.74 cM Incorrect distance =

½(4,516 + 4,652) + 3×(232)

9,400

4,584 + 696

9,400

5,280

9,400

= 0.5617 = 56.17 cM Incorrect MC

3728_2a84

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is affiliated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene W is related to the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

1,902

2,828

TOTAL =

4,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and W

distance =

½(70) + 3×(70)

4,800

35 + 210

4,800

245

4,800

= 0.0510 = 5.10 cM Incorrect distance =

½(1,902 + 2,828) + 3×(70)

4,800

2,365 + 210

4,800

2,575

4,800

= 0.5365 = 53.65 cM Incorrect distance =

½(0) + 3×(70)

4,800

0 + 210

4,800

210

4,800

= 0.0437 = 4.38 cM Incorrect distance =

½(1,902) + 3×(70)

4,800

951 + 210

4,800

1,161

4,800

= 0.2419 = 24.19 cM Correct distance =

½(2,828) + 3×(70)

4,800

1,414 + 210

4,800

1,624

4,800

= 0.3383 = 33.83 cM Incorrect distance =

½(2,828) + 3×(0)

4,800

1,414 + 0

4,800

1,414

4,800

= 0.2946 = 29.46 cM Incorrect MC

cb90_5484

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene H is connected with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.
Gene X is affiliated with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

109

2,412

2,879

TOTAL =

5,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes H and X

distance =

½(2,412 + 2,879) + 3×(109)

5,400

2645.5 + 327

5,400

2972.5

5,400

= 0.5505 = 55.05 cM Incorrect distance =

½(0) + 3×(109)

5,400

0 + 327

5,400

327

5,400

= 0.0606 = 6.06 cM Incorrect distance =

½(2,879) + 3×(109)

5,400

1439.5 + 327

5,400

1766.5

5,400

= 0.3271 = 32.71 cM Incorrect distance =

½(109) + 3×(0)

5,400

54.5 + 0

5,400

54.5

5,400

= 0.0101 = 1.01 cM Incorrect distance =

½(109) + 3×(109)

5,400

54.5 + 327

5,400

381.5

5,400

= 0.0706 = 7.06 cM Incorrect distance =

½(2,412) + 3×(109)

5,400

1,206 + 327

5,400

1,533

5,400

= 0.2839 = 28.39 cM Correct MC

c776_ef90

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene R is correlated with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.
Gene T is associated with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

3,131

2,924

145

TOTAL =

6,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes R and T

distance =

½(2,924 + 3,131) + 3×(145)

6,200

3027.5 + 435

6,200

3462.5

6,200

= 0.5585 = 55.85 cM Incorrect distance =

½(2,924) + 3×(145)

6,200

1,462 + 435

6,200

1,897

6,200

= 0.3060 = 30.60 cM Correct distance =

½(3,131) + 3×(0)

6,200

1565.5 + 0

6,200

1565.5

6,200

= 0.2525 = 25.25 cM Incorrect distance =

½(145) + 3×(145)

6,200

72.5 + 435

6,200

507.5

6,200

= 0.0819 = 8.19 cM Incorrect distance =

½(2,924) + 3×(0)

6,200

1,462 + 0

6,200

1,462

6,200

= 0.2358 = 23.58 cM Incorrect distance =

½(145) + 3×(0)

6,200

72.5 + 0

6,200

72.5

6,200

= 0.0117 = 1.17 cM Incorrect MC

9cb1_5a8d

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene H is linked with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.
Gene Y is affiliated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

5,845

3,254

101

TOTAL =

9,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes H and Y

distance =

½(3,254) + 3×(101)

9,200

1,627 + 303

9,200

1,930

9,200

= 0.2098 = 20.98 cM Correct distance =

½(3,254) + 3×(0)

9,200

1,627 + 0

9,200

1,627

9,200

= 0.1768 = 17.68 cM Incorrect distance =

½(3,254 + 5,845) + 3×(101)

9,200

4549.5 + 303

9,200

4852.5

9,200

= 0.5274 = 52.74 cM Incorrect distance =

½(101) + 3×(101)

9,200

50.5 + 303

9,200

353.5

9,200

= 0.0384 = 3.84 cM Incorrect distance =

½(5,845) + 3×(101)

9,200

2922.5 + 303

9,200

3225.5

9,200

= 0.3506 = 35.06 cM Incorrect distance =

½(101) + 3×(0)

9,200

50.5 + 0

9,200

50.5

9,200

= 0.0055 = 0.55 cM Incorrect MC

e714_7120

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is correlated with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene W is affiliated with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

1,309

1,230

TOTAL =

2,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and W

distance =

½(1,230) + 3×(61)

2,600

615 + 183

2,600

798

2,600

= 0.3069 = 30.69 cM Correct distance =

½(1,230) + 3×(0)

2,600

615 + 0

2,600

615

2,600

= 0.2365 = 23.65 cM Incorrect distance =

½(0) + 3×(61)

2,600

0 + 183

2,600

183

2,600

= 0.0704 = 7.04 cM Incorrect distance =

½(61) + 3×(61)

2,600

30.5 + 183

2,600

213.5

2,600

= 0.0821 = 8.21 cM Incorrect distance =

½(61) + 3×(0)

2,600

30.5 + 0

2,600

30.5

2,600

= 0.0117 = 1.17 cM Incorrect distance =

½(1,309) + 3×(61)

2,600

654.5 + 183

2,600

837.5

2,600

= 0.3221 = 32.21 cM Incorrect MC

882d_9558

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene J is linked with the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.
Gene Y is associated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

2,400

2,102

TOTAL =

4,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes J and Y

distance =

½(98) + 3×(0)

4,600

49 + 0

4,600

= 0.0107 = 1.07 cM Incorrect distance =

½(98) + 3×(98)

4,600

49 + 294

4,600

343

4,600

= 0.0746 = 7.46 cM Incorrect distance =

½(2,400) + 3×(0)

4,600

1,200 + 0

4,600

1,200

4,600

= 0.2609 = 26.09 cM Incorrect distance =

½(2,102 + 2,400) + 3×(98)

4,600

2,251 + 294

4,600

2,545

4,600

= 0.5533 = 55.33 cM Incorrect distance =

½(2,102) + 3×(0)

4,600

1,051 + 0

4,600

1,051

4,600

= 0.2285 = 22.85 cM Incorrect distance =

½(2,102) + 3×(98)

4,600

1,051 + 294

4,600

1,345

4,600

= 0.2924 = 29.24 cM Correct MC

d214_3c21

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is connected with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene P is analogous to the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

129

2,922

3,549

TOTAL =

6,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and P

distance =

½(129) + 3×(0)

6,600

64.5 + 0

6,600

64.5

6,600

= 0.0098 = 0.98 cM Incorrect distance =

½(2,922) + 3×(0)

6,600

1,461 + 0

6,600

1,461

6,600

= 0.2214 = 22.14 cM Incorrect distance =

½(3,549) + 3×(0)

6,600

1774.5 + 0

6,600

1774.5

6,600

= 0.2689 = 26.89 cM Incorrect distance =

½(2,922) + 3×(129)

6,600

1,461 + 387

6,600

1,848

6,600

= 0.2800 = 28 cM Correct distance =

½(2,922 + 3,549) + 3×(129)

6,600

3235.5 + 387

6,600

3622.5

6,600

= 0.5489 = 54.89 cM Incorrect distance =

½(129) + 3×(129)

6,600

64.5 + 387

6,600

451.5

6,600

= 0.0684 = 6.84 cM Incorrect MC

8aca_b819

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene H is linked with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.
Gene K is connected with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.

Set #

Tetrad Genotypes

Progeny
Count

3,552

2,548

100

TOTAL =

6,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes H and K

distance =

½(2,548) + 3×(100)

6,200

1,274 + 300

6,200

1,574

6,200

= 0.2539 = 25.39 cM Correct distance =

½(2,548 + 3,552) + 3×(100)

6,200

3,050 + 300

6,200

3,350

6,200

= 0.5403 = 54.03 cM Incorrect distance =

½(3,552) + 3×(100)

6,200

1,776 + 300

6,200

2,076

6,200

= 0.3348 = 33.48 cM Incorrect distance =

½(0) + 3×(100)

6,200

0 + 300

6,200

300

6,200

= 0.0484 = 4.84 cM Incorrect distance =

½(3,552) + 3×(0)

6,200

1,776 + 0

6,200

1,776

6,200

= 0.2865 = 28.65 cM Incorrect distance =

½(100) + 3×(100)

6,200

50 + 300

6,200

350

6,200

= 0.0565 = 5.65 cM Incorrect MC

fad1_0cd1

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene W is connected with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.
Gene X is linked with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

1,773

996

TOTAL =

2,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes W and X

distance =

½(1,773) + 3×(31)

2,800

886.5 + 93

2,800

979.5

2,800

= 0.3498 = 34.98 cM Incorrect distance =

½(31) + 3×(0)

2,800

15.5 + 0

2,800

15.5

2,800

= 0.0055 = 0.55 cM Incorrect distance =

½(1,773) + 3×(0)

2,800

886.5 + 0

2,800

886.5

2,800

= 0.3166 = 31.66 cM Incorrect distance =

½(996) + 3×(31)

2,800

498 + 93

2,800

591

2,800

= 0.2111 = 21.11 cM Correct distance =

½(996 + 1,773) + 3×(31)

2,800

1384.5 + 93

2,800

1477.5

2,800

= 0.5277 = 52.77 cM Incorrect distance =

½(996) + 3×(0)

2,800

498 + 0

2,800

498

2,800

= 0.1779 = 17.79 cM Incorrect MC

297a_abc2

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene T is correlated with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.
Gene W is analogous to the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

2,863

1,870

TOTAL =

4,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes T and W

distance =

½(67) + 3×(67)

4,800

33.5 + 201

4,800

234.5

4,800

= 0.0489 = 4.89 cM Incorrect distance =

½(1,870 + 2,863) + 3×(67)

4,800

2366.5 + 201

4,800

2567.5

4,800

= 0.5349 = 53.49 cM Incorrect distance =

½(0) + 3×(67)

4,800

0 + 201

4,800

201

4,800

= 0.0419 = 4.19 cM Incorrect distance =

½(1,870) + 3×(67)

4,800

935 + 201

4,800

1,136

4,800

= 0.2367 = 23.67 cM Correct distance =

½(1,870) + 3×(0)

4,800

935 + 0

4,800

935

4,800

= 0.1948 = 19.48 cM Incorrect distance =

½(2,863) + 3×(0)

4,800

1431.5 + 0

4,800

1431.5

4,800

= 0.2982 = 29.82 cM Incorrect MC

6706_52e1

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is linked with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene R is associated with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

2,158

1,204

TOTAL =

3,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and R

distance =

½(38) + 3×(0)

3,400

19 + 0

3,400

= 0.0056 = 0.56 cM Incorrect distance =

½(2,158) + 3×(0)

3,400

1,079 + 0

3,400

1,079

3,400

= 0.3174 = 31.74 cM Incorrect distance =

½(1,204 + 2,158) + 3×(38)

3,400

1,681 + 114

3,400

1,795

3,400

= 0.5279 = 52.79 cM Incorrect distance =

½(1,204) + 3×(0)

3,400

602 + 0

3,400

602

3,400

= 0.1771 = 17.71 cM Incorrect distance =

½(0) + 3×(38)

3,400

0 + 114

3,400

114

3,400

= 0.0335 = 3.35 cM Incorrect distance =

½(1,204) + 3×(38)

3,400

602 + 114

3,400

716

3,400

= 0.2106 = 21.06 cM Correct MC

b533_48a9

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is correlated with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene T is affiliated with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

718

850

TOTAL =

1,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and T

distance =

½(32) + 3×(32)

1,600

16 + 96

1,600

112

1,600

= 0.0700 = 7 cM Incorrect distance =

½(718 + 850) + 3×(32)

1,600

784 + 96

1,600

880

1,600

= 0.5500 = 55 cM Incorrect distance =

½(850) + 3×(32)

1,600

425 + 96

1,600

521

1,600

= 0.3256 = 32.56 cM Incorrect distance =

½(718) + 3×(32)

1,600

359 + 96

1,600

455

1,600

= 0.2844 = 28.44 cM Correct distance =

½(32) + 3×(0)

1,600

16 + 0

1,600

= 0.0100 = 1 cM Incorrect distance =

½(850) + 3×(0)

1,600

425 + 0

1,600

425

1,600

= 0.2656 = 26.56 cM Incorrect MC

bdd3_97d8

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene T is correlated with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.
Gene Y is affiliated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

4,730

2,780

TOTAL =

7,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes T and Y

distance =

½(2,780) + 3×(90)

7,600

1,390 + 270

7,600

1,660

7,600

= 0.2184 = 21.84 cM Correct distance =

½(4,730) + 3×(90)

7,600

2,365 + 270

7,600

2,635

7,600

= 0.3467 = 34.67 cM Incorrect distance =

½(0) + 3×(90)

7,600

0 + 270

7,600

270

7,600

= 0.0355 = 3.55 cM Incorrect distance =

½(4,730) + 3×(0)

7,600

2,365 + 0

7,600

2,365

7,600

= 0.3112 = 31.12 cM Incorrect distance =

½(2,780 + 4,730) + 3×(90)

7,600

3,755 + 270

7,600

4,025

7,600

= 0.5296 = 52.96 cM Incorrect distance =

½(90) + 3×(90)

7,600

45 + 270

7,600

315

7,600

= 0.0414 = 4.14 cM Incorrect MC

ae6e_136f

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is analogous to the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene H is related to the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

496

889

TOTAL =

1,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and H

distance =

½(15) + 3×(15)

1,400

7.5 + 45

1,400

52.5

1,400

= 0.0375 = 3.75 cM Incorrect distance =

½(496) + 3×(15)

1,400

248 + 45

1,400

293

1,400

= 0.2093 = 20.93 cM Correct distance =

½(889) + 3×(0)

1,400

444.5 + 0

1,400

444.5

1,400

= 0.3175 = 31.75 cM Incorrect distance =

½(496) + 3×(0)

1,400

248 + 0

1,400

248

1,400

= 0.1771 = 17.71 cM Incorrect distance =

½(15) + 3×(0)

1,400

7.5 + 0

1,400

7.5

1,400

= 0.0054 = 0.54 cM Incorrect distance =

½(496 + 889) + 3×(15)

1,400

692.5 + 45

1,400

737.5

1,400

= 0.5268 = 52.68 cM Incorrect MC

b40a_d170

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is connected with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene H is affiliated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

1,969

1,748

TOTAL =

3,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and H

distance =

½(0) + 3×(83)

3,800

0 + 249

3,800

249

3,800

= 0.0655 = 6.55 cM Incorrect distance =

½(1,969) + 3×(83)

3,800

984.5 + 249

3,800

1233.5

3,800

= 0.3246 = 32.46 cM Incorrect distance =

½(83) + 3×(0)

3,800

41.5 + 0

3,800

41.5

3,800

= 0.0109 = 1.09 cM Incorrect distance =

½(1,969) + 3×(0)

3,800

984.5 + 0

3,800

984.5

3,800

= 0.2591 = 25.91 cM Incorrect distance =

½(1,748) + 3×(83)

3,800

874 + 249

3,800

1,123

3,800

= 0.2955 = 29.55 cM Correct distance =

½(1,748 + 1,969) + 3×(83)

3,800

1858.5 + 249

3,800

2107.5

3,800

= 0.5546 = 55.46 cM Incorrect MC

9374_3fd5

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene J is correlated with the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.
Gene R is analogous to the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

5,927

3,366

107

TOTAL =

9,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes J and R

distance =

½(107) + 3×(107)

9,400

53.5 + 321

9,400

374.5

9,400

= 0.0398 = 3.98 cM Incorrect distance =

½(3,366) + 3×(107)

9,400

1,683 + 321

9,400

2,004

9,400

= 0.2132 = 21.32 cM Correct distance =

½(3,366) + 3×(0)

9,400

1,683 + 0

9,400

1,683

9,400

= 0.1790 = 17.90 cM Incorrect distance =

½(5,927) + 3×(107)

9,400

2963.5 + 321

9,400

3284.5

9,400

= 0.3494 = 34.94 cM Incorrect distance =

½(5,927) + 3×(0)

9,400

2963.5 + 0

9,400

2963.5

9,400

= 0.3153 = 31.53 cM Incorrect distance =

½(107) + 3×(0)

9,400

53.5 + 0

9,400

53.5

9,400

= 0.0057 = 0.57 cM Incorrect MC

e344_4abc

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is associated with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene H is connected with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

176

3,864

4,560

TOTAL =

8,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and H

distance =

½(176) + 3×(0)

8,600

88 + 0

8,600

= 0.0102 = 1.02 cM Incorrect distance =

½(3,864) + 3×(176)

8,600

1,932 + 528

8,600

2,460

8,600

= 0.2860 = 28.60 cM Correct distance =

½(0) + 3×(176)

8,600

0 + 528

8,600

528

8,600

= 0.0614 = 6.14 cM Incorrect distance =

½(3,864) + 3×(0)

8,600

1,932 + 0

8,600

1,932

8,600

= 0.2247 = 22.47 cM Incorrect distance =

½(176) + 3×(176)

8,600

88 + 528

8,600

616

8,600

= 0.0716 = 7.16 cM Incorrect distance =

½(3,864 + 4,560) + 3×(176)

8,600

4,212 + 528

8,600

4,740

8,600

= 0.5512 = 55.12 cM Incorrect MC

bc9b_d09b

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is affiliated with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene K is connected with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.

Set #

Tetrad Genotypes

Progeny
Count

5,238

3,250

112

TOTAL =

8,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and K

distance =

½(0) + 3×(112)

8,600

0 + 336

8,600

336

8,600

= 0.0391 = 3.91 cM Incorrect distance =

½(3,250 + 5,238) + 3×(112)

8,600

4,244 + 336

8,600

4,580

8,600

= 0.5326 = 53.26 cM Incorrect distance =

½(5,238) + 3×(0)

8,600

2,619 + 0

8,600

2,619

8,600

= 0.3045 = 30.45 cM Incorrect distance =

½(3,250) + 3×(112)

8,600

1,625 + 336

8,600

1,961

8,600

= 0.2280 = 22.80 cM Correct distance =

½(112) + 3×(112)

8,600

56 + 336

8,600

392

8,600

= 0.0456 = 4.56 cM Incorrect distance =

½(112) + 3×(0)

8,600

56 + 0

8,600

= 0.0065 = 0.65 cM Incorrect MC

741b_1684

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is connected with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene H is correlated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

4,758

2,564

TOTAL =

7,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and H

distance =

½(2,564) + 3×(78)

7,400

1,282 + 234

7,400

1,516

7,400

= 0.2049 = 20.49 cM Correct distance =

½(4,758) + 3×(78)

7,400

2,379 + 234

7,400

2,613

7,400

= 0.3531 = 35.31 cM Incorrect distance =

½(78) + 3×(0)

7,400

39 + 0

7,400

= 0.0053 = 0.53 cM Incorrect distance =

½(2,564 + 4,758) + 3×(78)

7,400

3,661 + 234

7,400

3,895

7,400

= 0.5264 = 52.64 cM Incorrect distance =

½(4,758) + 3×(0)

7,400

2,379 + 0

7,400

2,379

7,400

= 0.3215 = 32.15 cM Incorrect distance =

½(78) + 3×(78)

7,400

39 + 234

7,400

273

7,400

= 0.0369 = 3.69 cM Incorrect MC

6038_680f

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is connected with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene K is associated with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.

Set #

Tetrad Genotypes

Progeny
Count

4,218

3,616

166

TOTAL =

8,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and K

distance =

½(4,218) + 3×(0)

8,000

2,109 + 0

8,000

2,109

8,000

= 0.2636 = 26.36 cM Incorrect distance =

½(3,616 + 4,218) + 3×(166)

8,000

3,917 + 498

8,000

4,415

8,000

= 0.5519 = 55.19 cM Incorrect distance =

½(0) + 3×(166)

8,000

0 + 498

8,000

498

8,000

= 0.0622 = 6.22 cM Incorrect distance =

½(3,616) + 3×(166)

8,000

1,808 + 498

8,000

2,306

8,000

= 0.2883 = 28.82 cM Correct distance =

½(4,218) + 3×(166)

8,000

2,109 + 498

8,000

2,607

8,000

= 0.3259 = 32.59 cM Incorrect distance =

½(166) + 3×(0)

8,000

83 + 0

8,000

= 0.0104 = 1.04 cM Incorrect MC

d3f7_18d7

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is connected with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene N is linked with the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

142

3,406

4,452

TOTAL =

8,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and N

distance =

½(142) + 3×(0)

8,000

71 + 0

8,000

= 0.0089 = 0.89 cM Incorrect distance =

½(3,406) + 3×(142)

8,000

1,703 + 426

8,000

2,129

8,000

= 0.2661 = 26.61 cM Correct distance =

½(4,452) + 3×(142)

8,000

2,226 + 426

8,000

2,652

8,000

= 0.3315 = 33.15 cM Incorrect distance =

½(142) + 3×(142)

8,000

71 + 426

8,000

497

8,000

= 0.0621 = 6.21 cM Incorrect distance =

½(3,406) + 3×(0)

8,000

1,703 + 0

8,000

1,703

8,000

= 0.2129 = 21.29 cM Incorrect distance =

½(0) + 3×(142)

8,000

0 + 426

8,000

426

8,000

= 0.0532 = 5.33 cM Incorrect MC

e2de_a184

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is associated with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene N is associated with the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

2,364

3,140

TOTAL =

5,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and N

distance =

½(96) + 3×(0)

5,600

48 + 0

5,600

= 0.0086 = 0.86 cM Incorrect distance =

½(2,364) + 3×(96)

5,600

1,182 + 288

5,600

1,470

5,600

= 0.2625 = 26.25 cM Correct distance =

½(0) + 3×(96)

5,600

0 + 288

5,600

288

5,600

= 0.0514 = 5.14 cM Incorrect distance =

½(96) + 3×(96)

5,600

48 + 288

5,600

336

5,600

= 0.0600 = 6 cM Incorrect distance =

½(2,364) + 3×(0)

5,600

1,182 + 0

5,600

1,182

5,600

= 0.2111 = 21.11 cM Incorrect distance =

½(2,364 + 3,140) + 3×(96)

5,600

2,752 + 288

5,600

3,040

5,600

= 0.5429 = 54.29 cM Incorrect MC

f8a7_ef66

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is affiliated with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene M is related to the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

1,398

1,534

TOTAL =

3,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and M

distance =

½(1,398) + 3×(0)

3,000

699 + 0

3,000

699

3,000

= 0.2330 = 23.30 cM Incorrect distance =

½(68) + 3×(68)

3,000

34 + 204

3,000

238

3,000

= 0.0793 = 7.93 cM Incorrect distance =

½(68) + 3×(0)

3,000

34 + 0

3,000

= 0.0113 = 1.13 cM Incorrect distance =

½(1,398) + 3×(68)

3,000

699 + 204

3,000

903

3,000

= 0.3010 = 30.10 cM Correct distance =

½(1,534) + 3×(68)

3,000

767 + 204

3,000

971

3,000

= 0.3237 = 32.37 cM Incorrect distance =

½(1,398 + 1,534) + 3×(68)

3,000

1,466 + 204

3,000

1,670

3,000

= 0.5567 = 55.67 cM Incorrect MC

0314_1a03

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene R is affiliated with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.
Gene X is connected with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

3,775

2,904

121

TOTAL =

6,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes R and X

distance =

½(3,775) + 3×(0)

6,800

1887.5 + 0

6,800

1887.5

6,800

= 0.2776 = 27.76 cM Incorrect distance =

½(2,904) + 3×(0)

6,800

1,452 + 0

6,800

1,452

6,800

= 0.2135 = 21.35 cM Incorrect distance =

½(121) + 3×(0)

6,800

60.5 + 0

6,800

60.5

6,800

= 0.0089 = 0.89 cM Incorrect distance =

½(0) + 3×(121)

6,800

0 + 363

6,800

363

6,800

= 0.0534 = 5.34 cM Incorrect distance =

½(2,904) + 3×(121)

6,800

1,452 + 363

6,800

1,815

6,800

= 0.2669 = 26.69 cM Correct distance =

½(121) + 3×(121)

6,800

60.5 + 363

6,800

423.5

6,800

= 0.0623 = 6.23 cM Incorrect MC

6ff9_e291

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is connected with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene H is analogous to the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

2,640

4,677

TOTAL =

7,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and H

distance =

½(2,640) + 3×(0)

7,400

1,320 + 0

7,400

1,320

7,400

= 0.1784 = 17.84 cM Incorrect distance =

½(83) + 3×(0)

7,400

41.5 + 0

7,400

41.5

7,400

= 0.0056 = 0.56 cM Incorrect distance =

½(2,640) + 3×(83)

7,400

1,320 + 249

7,400

1,569

7,400

= 0.2120 = 21.20 cM Correct distance =

½(4,677) + 3×(0)

7,400

2338.5 + 0

7,400

2338.5

7,400

= 0.3160 = 31.60 cM Incorrect distance =

½(2,640 + 4,677) + 3×(83)

7,400

3658.5 + 249

7,400

3907.5

7,400

= 0.5280 = 52.80 cM Incorrect distance =

½(83) + 3×(83)

7,400

41.5 + 249

7,400

290.5

7,400

= 0.0393 = 3.93 cM Incorrect MC

6e7b_b750

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is analogous to the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene F is connected with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.

Set #

Tetrad Genotypes

Progeny
Count

1,962

1,936

102

TOTAL =

4,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and F

distance =

½(102) + 3×(102)

4,000

51 + 306

4,000

357

4,000

= 0.0892 = 8.92 cM Incorrect distance =

½(1,962) + 3×(0)

4,000

981 + 0

4,000

981

4,000

= 0.2452 = 24.52 cM Incorrect distance =

½(1,962) + 3×(102)

4,000

981 + 306

4,000

1,287

4,000

= 0.3217 = 32.17 cM Incorrect distance =

½(1,936) + 3×(102)

4,000

968 + 306

4,000

1,274

4,000

= 0.3185 = 31.85 cM Correct distance =

½(102) + 3×(0)

4,000

51 + 0

4,000

= 0.0127 = 1.27 cM Incorrect distance =

½(1,936) + 3×(0)

4,000

968 + 0

4,000

968

4,000

= 0.2420 = 24.20 cM Incorrect MC

89e0_c188

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene J is related to the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.
Gene M is related to the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

2,840

2,448

112

TOTAL =

5,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes J and M

distance =

½(112) + 3×(0)

5,400

56 + 0

5,400

= 0.0104 = 1.04 cM Incorrect distance =

½(2,448) + 3×(112)

5,400

1,224 + 336

5,400

1,560

5,400

= 0.2889 = 28.89 cM Correct distance =

½(2,840) + 3×(0)

5,400

1,420 + 0

5,400

1,420

5,400

= 0.2630 = 26.30 cM Incorrect distance =

½(2,448) + 3×(0)

5,400

1,224 + 0

5,400

1,224

5,400

= 0.2267 = 22.67 cM Incorrect distance =

½(2,840) + 3×(112)

5,400

1,420 + 336

5,400

1,756

5,400

= 0.3252 = 32.52 cM Incorrect distance =

½(0) + 3×(112)

5,400

0 + 336

5,400

336

5,400

= 0.0622 = 6.22 cM Incorrect MC

6fc1_4711

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is analogous to the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene R is affiliated with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

1,493

1,066

TOTAL =

2,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and R

distance =

½(1,493) + 3×(0)

2,600

746.5 + 0

2,600

746.5

2,600

= 0.2871 = 28.71 cM Incorrect distance =

½(1,066) + 3×(41)

2,600

533 + 123

2,600

656

2,600

= 0.2523 = 25.23 cM Correct distance =

½(0) + 3×(41)

2,600

0 + 123

2,600

123

2,600

= 0.0473 = 4.73 cM Incorrect distance =

½(1,493) + 3×(41)

2,600

746.5 + 123

2,600

869.5

2,600

= 0.3344 = 33.44 cM Incorrect distance =

½(41) + 3×(0)

2,600

20.5 + 0

2,600

20.5

2,600

= 0.0079 = 0.79 cM Incorrect distance =

½(1,066) + 3×(0)

2,600

533 + 0

2,600

533

2,600

= 0.2050 = 20.50 cM Incorrect MC

35d6_06f4

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is affiliated with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene M is correlated with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

1,389

786

TOTAL =

2,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and M

distance =

½(1,389) + 3×(0)

2,200

694.5 + 0

2,200

694.5

2,200

= 0.3157 = 31.57 cM Incorrect distance =

½(786) + 3×(0)

2,200

393 + 0

2,200

393

2,200

= 0.1786 = 17.86 cM Incorrect distance =

½(786) + 3×(25)

2,200

393 + 75

2,200

468

2,200

= 0.2127 = 21.27 cM Correct distance =

½(25) + 3×(25)

2,200

12.5 + 75

2,200

87.5

2,200

= 0.0398 = 3.98 cM Incorrect distance =

½(0) + 3×(25)

2,200

0 + 75

2,200

= 0.0341 = 3.41 cM Incorrect distance =

½(1,389) + 3×(25)

2,200

694.5 + 75

2,200

769.5

2,200

= 0.3498 = 34.98 cM Incorrect MC

fb4c_3f6e

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is correlated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene J is connected with the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.

Set #

Tetrad Genotypes

Progeny
Count

1,162

1,177

TOTAL =

2,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and J

distance =

½(1,162 + 1,177) + 3×(61)

2,400

1169.5 + 183

2,400

1352.5

2,400

= 0.5635 = 56.35 cM Incorrect distance =

½(61) + 3×(61)

2,400

30.5 + 183

2,400

213.5

2,400

= 0.0890 = 8.90 cM Incorrect distance =

½(0) + 3×(61)

2,400

0 + 183

2,400

183

2,400

= 0.0762 = 7.62 cM Incorrect distance =

½(61) + 3×(0)

2,400

30.5 + 0

2,400

30.5

2,400

= 0.0127 = 1.27 cM Incorrect distance =

½(1,177) + 3×(0)

2,400

588.5 + 0

2,400

588.5

2,400

= 0.2452 = 24.52 cM Incorrect distance =

½(1,162) + 3×(61)

2,400

581 + 183

2,400

764

2,400

= 0.3183 = 31.83 cM Correct MC

c0c2_1956

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is related to the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene H is correlated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

2,204

1,350

TOTAL =

3,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and H

distance =

½(2,204) + 3×(0)

3,600

1,102 + 0

3,600

1,102

3,600

= 0.3061 = 30.61 cM Incorrect distance =

½(46) + 3×(0)

3,600

23 + 0

3,600

= 0.0064 = 0.64 cM Incorrect distance =

½(1,350) + 3×(46)

3,600

675 + 138

3,600

813

3,600

= 0.2258 = 22.58 cM Correct distance =

½(1,350 + 2,204) + 3×(46)

3,600

1,777 + 138

3,600

1,915

3,600

= 0.5319 = 53.19 cM Incorrect distance =

½(2,204) + 3×(46)

3,600

1,102 + 138

3,600

1,240

3,600

= 0.3444 = 34.44 cM Incorrect distance =

½(46) + 3×(46)

3,600

23 + 138

3,600

161

3,600

= 0.0447 = 4.47 cM Incorrect MC

b673_e72d

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene R is analogous to the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.
Gene Y is affiliated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

2,260

3,867

TOTAL =

6,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes R and Y

distance =

½(3,867) + 3×(0)

6,200

1933.5 + 0

6,200

1933.5

6,200

= 0.3119 = 31.19 cM Incorrect distance =

½(73) + 3×(73)

6,200

36.5 + 219

6,200

255.5

6,200

= 0.0412 = 4.12 cM Incorrect distance =

½(0) + 3×(73)

6,200

0 + 219

6,200

219

6,200

= 0.0353 = 3.53 cM Incorrect distance =

½(3,867) + 3×(73)

6,200

1933.5 + 219

6,200

2152.5

6,200

= 0.3472 = 34.72 cM Incorrect distance =

½(2,260 + 3,867) + 3×(73)

6,200

3063.5 + 219

6,200

3282.5

6,200

= 0.5294 = 52.94 cM Incorrect distance =

½(2,260) + 3×(73)

6,200

1,130 + 219

6,200

1,349

6,200

= 0.2176 = 21.76 cM Correct MC

7507_f06a

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene W is connected with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.
Gene X is correlated with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

1,846

2,479

TOTAL =

4,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes W and X

distance =

½(0) + 3×(75)

4,400

0 + 225

4,400

225

4,400

= 0.0511 = 5.11 cM Incorrect distance =

½(1,846) + 3×(75)

4,400

923 + 225

4,400

1,148

4,400

= 0.2609 = 26.09 cM Correct distance =

½(2,479) + 3×(75)

4,400

1239.5 + 225

4,400

1464.5

4,400

= 0.3328 = 33.28 cM Incorrect distance =

½(2,479) + 3×(0)

4,400

1239.5 + 0

4,400

1239.5

4,400

= 0.2817 = 28.17 cM Incorrect distance =

½(75) + 3×(75)

4,400

37.5 + 225

4,400

262.5

4,400

= 0.0597 = 5.97 cM Incorrect distance =

½(1,846) + 3×(0)

4,400

923 + 0

4,400

923

4,400

= 0.2098 = 20.98 cM Incorrect MC

9c73_fbc3

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene J is correlated with the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.
Gene X is affiliated with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

2,278

3,028

TOTAL =

5,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes J and X

distance =

½(94) + 3×(94)

5,400

47 + 282

5,400

329

5,400

= 0.0609 = 6.09 cM Incorrect distance =

½(2,278) + 3×(94)

5,400

1,139 + 282

5,400

1,421

5,400

= 0.2631 = 26.31 cM Correct distance =

½(2,278) + 3×(0)

5,400

1,139 + 0

5,400

1,139

5,400

= 0.2109 = 21.09 cM Incorrect distance =

½(3,028) + 3×(0)

5,400

1,514 + 0

5,400

1,514

5,400

= 0.2804 = 28.04 cM Incorrect distance =

½(0) + 3×(94)

5,400

0 + 282

5,400

282

5,400

= 0.0522 = 5.22 cM Incorrect distance =

½(3,028) + 3×(94)

5,400

1,514 + 282

5,400

1,796

5,400

= 0.3326 = 33.26 cM Incorrect MC

ecc1_e28c

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is associated with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene X is analogous to the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

1,254

1,901

TOTAL =

3,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and X

distance =

½(1,254) + 3×(0)

3,200

627 + 0

3,200

627

3,200

= 0.1959 = 19.59 cM Incorrect distance =

½(0) + 3×(45)

3,200

0 + 135

3,200

135

3,200

= 0.0422 = 4.22 cM Incorrect distance =

½(1,254) + 3×(45)

3,200

627 + 135

3,200

762

3,200

= 0.2381 = 23.81 cM Correct distance =

½(45) + 3×(45)

3,200

22.5 + 135

3,200

157.5

3,200

= 0.0492 = 4.92 cM Incorrect distance =

½(1,901) + 3×(45)

3,200

950.5 + 135

3,200

1085.5

3,200

= 0.3392 = 33.92 cM Incorrect distance =

½(1,901) + 3×(0)

3,200

950.5 + 0

3,200

950.5

3,200

= 0.2970 = 29.70 cM Incorrect MC

17e2_9413

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene P is related to the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.
Gene R is affiliated with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

1,770

998

TOTAL =

2,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes P and R

distance =

½(998) + 3×(0)

2,800

499 + 0

2,800

499

2,800

= 0.1782 = 17.82 cM Incorrect distance =

½(1,770) + 3×(0)

2,800

885 + 0

2,800

885

2,800

= 0.3161 = 31.61 cM Incorrect distance =

½(998 + 1,770) + 3×(32)

2,800

1,384 + 96

2,800

1,480

2,800

= 0.5286 = 52.86 cM Incorrect distance =

½(998) + 3×(32)

2,800

499 + 96

2,800

595

2,800

= 0.2125 = 21.25 cM Correct distance =

½(32) + 3×(32)

2,800

16 + 96

2,800

112

2,800

= 0.0400 = 4 cM Incorrect distance =

½(0) + 3×(32)

2,800

0 + 96

2,800

= 0.0343 = 3.43 cM Incorrect MC

9751_20d2

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is associated with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene W is analogous to the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

4,150

2,750

100

TOTAL =

7,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and W

distance =

½(100) + 3×(100)

7,000

50 + 300

7,000

350

7,000

= 0.0500 = 5 cM Incorrect distance =

½(2,750) + 3×(0)

7,000

1,375 + 0

7,000

1,375

7,000

= 0.1964 = 19.64 cM Incorrect distance =

½(2,750) + 3×(100)

7,000

1,375 + 300

7,000

1,675

7,000

= 0.2393 = 23.93 cM Correct distance =

½(2,750 + 4,150) + 3×(100)

7,000

3,450 + 300

7,000

3,750

7,000

= 0.5357 = 53.57 cM Incorrect distance =

½(4,150) + 3×(0)

7,000

2,075 + 0

7,000

2,075

7,000

= 0.2964 = 29.64 cM Incorrect distance =

½(100) + 3×(0)

7,000

50 + 0

7,000

= 0.0071 = 0.71 cM Incorrect MC

c6a1_060e

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is correlated with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene H is affiliated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

2,522

1,808

TOTAL =

4,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and H

distance =

½(2,522) + 3×(70)

4,400

1,261 + 210

4,400

1,471

4,400

= 0.3343 = 33.43 cM Incorrect distance =

½(70) + 3×(0)

4,400

35 + 0

4,400

= 0.0080 = 0.80 cM Incorrect distance =

½(0) + 3×(70)

4,400

0 + 210

4,400

210

4,400

= 0.0477 = 4.77 cM Incorrect distance =

½(1,808) + 3×(70)

4,400

904 + 210

4,400

1,114

4,400

= 0.2532 = 25.32 cM Correct distance =

½(1,808 + 2,522) + 3×(70)

4,400

2,165 + 210

4,400

2,375

4,400

= 0.5398 = 53.98 cM Incorrect distance =

½(1,808) + 3×(0)

4,400

904 + 0

4,400

904

4,400

= 0.2055 = 20.55 cM Incorrect MC

2d5d_2b4b

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene H is analogous to the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.
Gene P is correlated with the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

4,680

3,572

148

TOTAL =

8,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes H and P

distance =

½(148) + 3×(148)

8,400

74 + 444

8,400

518

8,400

= 0.0617 = 6.17 cM Incorrect distance =

½(3,572) + 3×(0)

8,400

1,786 + 0

8,400

1,786

8,400

= 0.2126 = 21.26 cM Incorrect distance =

½(4,680) + 3×(0)

8,400

2,340 + 0

8,400

2,340

8,400

= 0.2786 = 27.86 cM Incorrect distance =

½(3,572) + 3×(148)

8,400

1,786 + 444

8,400

2,230

8,400

= 0.2655 = 26.55 cM Correct distance =

½(148) + 3×(0)

8,400

74 + 0

8,400

= 0.0088 = 0.88 cM Incorrect distance =

½(0) + 3×(148)

8,400

0 + 444

8,400

444

8,400

= 0.0529 = 5.29 cM Incorrect MC

ce71_9325

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is correlated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene E is connected with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.

Set #

Tetrad Genotypes

Progeny
Count

5,261

3,604

135

TOTAL =

9,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and E

distance =

½(3,604 + 5,261) + 3×(135)

9,000

4432.5 + 405

9,000

4837.5

9,000

= 0.5375 = 53.75 cM Incorrect distance =

½(3,604) + 3×(0)

9,000

1,802 + 0

9,000

1,802

9,000

= 0.2002 = 20.02 cM Incorrect distance =

½(3,604) + 3×(135)

9,000

1,802 + 405

9,000

2,207

9,000

= 0.2452 = 24.52 cM Correct distance =

½(0) + 3×(135)

9,000

0 + 405

9,000

405

9,000

= 0.0450 = 4.50 cM Incorrect distance =

½(5,261) + 3×(0)

9,000

2630.5 + 0

9,000

2630.5

9,000

= 0.2923 = 29.23 cM Incorrect distance =

½(135) + 3×(0)

9,000

67.5 + 0

9,000

67.5

9,000

= 0.0075 = 0.75 cM Incorrect MC

61cc_42bb

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene T is correlated with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.
Gene Y is analogous to the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

2,973

1,956

TOTAL =

5,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes T and Y

distance =

½(71) + 3×(71)

5,000

35.5 + 213

5,000

248.5

5,000

= 0.0497 = 4.97 cM Incorrect distance =

½(71) + 3×(0)

5,000

35.5 + 0

5,000

35.5

5,000

= 0.0071 = 0.71 cM Incorrect distance =

½(1,956) + 3×(0)

5,000

978 + 0

5,000

978

5,000

= 0.1956 = 19.56 cM Incorrect distance =

½(1,956 + 2,973) + 3×(71)

5,000

2464.5 + 213

5,000

2677.5

5,000

= 0.5355 = 53.55 cM Incorrect distance =

½(2,973) + 3×(0)

5,000

1486.5 + 0

5,000

1486.5

5,000

= 0.2973 = 29.73 cM Incorrect distance =

½(1,956) + 3×(71)

5,000

978 + 213

5,000

1,191

5,000

= 0.2382 = 23.82 cM Correct MC

dd33_63b9

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is affiliated with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene M is associated with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

2,448

2,058

TOTAL =

4,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and M

distance =

½(94) + 3×(0)

4,600

47 + 0

4,600

= 0.0102 = 1.02 cM Incorrect distance =

½(94) + 3×(94)

4,600

47 + 282

4,600

329

4,600

= 0.0715 = 7.15 cM Incorrect distance =

½(0) + 3×(94)

4,600

0 + 282

4,600

282

4,600

= 0.0613 = 6.13 cM Incorrect distance =

½(2,058) + 3×(0)

4,600

1,029 + 0

4,600

1,029

4,600

= 0.2237 = 22.37 cM Incorrect distance =

½(2,058) + 3×(94)

4,600

1,029 + 282

4,600

1,311

4,600

= 0.2850 = 28.50 cM Correct distance =

½(2,448) + 3×(0)

4,600

1,224 + 0

4,600

1,224

4,600

= 0.2661 = 26.61 cM Incorrect MC

59f7_a170

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is affiliated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene F is correlated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.

Set #

Tetrad Genotypes

Progeny
Count

2,120

2,587

TOTAL =

4,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and F

distance =

½(2,587) + 3×(93)

4,800

1293.5 + 279

4,800

1572.5

4,800

= 0.3276 = 32.76 cM Incorrect distance =

½(93) + 3×(93)

4,800

46.5 + 279

4,800

325.5

4,800

= 0.0678 = 6.78 cM Incorrect distance =

½(93) + 3×(0)

4,800

46.5 + 0

4,800

46.5

4,800

= 0.0097 = 0.97 cM Incorrect distance =

½(2,120) + 3×(93)

4,800

1,060 + 279

4,800

1,339

4,800

= 0.2790 = 27.90 cM Correct distance =

½(2,587) + 3×(0)

4,800

1293.5 + 0

4,800

1293.5

4,800

= 0.2695 = 26.95 cM Incorrect distance =

½(2,120) + 3×(0)

4,800

1,060 + 0

4,800

1,060

4,800

= 0.2208 = 22.08 cM Incorrect MC

9077_395c

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene H is associated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.
Gene R is linked with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

3,340

2,740

120

TOTAL =

6,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes H and R

distance =

½(3,340) + 3×(120)

6,200

1,670 + 360

6,200

2,030

6,200

= 0.3274 = 32.74 cM Incorrect distance =

½(2,740 + 3,340) + 3×(120)

6,200

3,040 + 360

6,200

3,400

6,200

= 0.5484 = 54.84 cM Incorrect distance =

½(120) + 3×(0)

6,200

60 + 0

6,200

= 0.0097 = 0.97 cM Incorrect distance =

½(0) + 3×(120)

6,200

0 + 360

6,200

360

6,200

= 0.0581 = 5.81 cM Incorrect distance =

½(2,740) + 3×(120)

6,200

1,370 + 360

6,200

1,730

6,200

= 0.2790 = 27.90 cM Correct distance =

½(120) + 3×(120)

6,200

60 + 360

6,200

420

6,200

= 0.0677 = 6.77 cM Incorrect MC

8ff7_2b9a

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is correlated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene D is related to the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.

Set #

Tetrad Genotypes

Progeny
Count

2,838

2,264

TOTAL =

5,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and D

distance =

½(0) + 3×(98)

5,200

0 + 294

5,200

294

5,200

= 0.0565 = 5.65 cM Incorrect distance =

½(2,264) + 3×(98)

5,200

1,132 + 294

5,200

1,426

5,200

= 0.2742 = 27.42 cM Correct distance =

½(2,264 + 2,838) + 3×(98)

5,200

2,551 + 294

5,200

2,845

5,200

= 0.5471 = 54.71 cM Incorrect distance =

½(2,838) + 3×(98)

5,200

1,419 + 294

5,200

1,713

5,200

= 0.3294 = 32.94 cM Incorrect distance =

½(2,264) + 3×(0)

5,200

1,132 + 0

5,200

1,132

5,200

= 0.2177 = 21.77 cM Incorrect distance =

½(2,838) + 3×(0)

5,200

1,419 + 0

5,200

1,419

5,200

= 0.2729 = 27.29 cM Incorrect MC

051d_000f

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene J is linked with the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.
Gene P is related to the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

640

536

TOTAL =

1,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes J and P

distance =

½(24) + 3×(0)

1,200

12 + 0

1,200

= 0.0100 = 1 cM Incorrect distance =

½(536) + 3×(24)

1,200

268 + 72

1,200

340

1,200

= 0.2833 = 28.33 cM Correct distance =

½(536 + 640) + 3×(24)

1,200

588 + 72

1,200

660

1,200

= 0.5500 = 55 cM Incorrect distance =

½(24) + 3×(24)

1,200

12 + 72

1,200

= 0.0700 = 7 cM Incorrect distance =

½(640) + 3×(24)

1,200

320 + 72

1,200

392

1,200

= 0.3267 = 32.67 cM Incorrect distance =

½(536) + 3×(0)

1,200

268 + 0

1,200

268

1,200

= 0.2233 = 22.33 cM Incorrect MC

6424_3c0c

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is analogous to the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene F is affiliated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.

Set #

Tetrad Genotypes

Progeny
Count

2,322

4,004

TOTAL =

6,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and F

distance =

½(74) + 3×(0)

6,400

37 + 0

6,400

= 0.0058 = 0.58 cM Incorrect distance =

½(2,322 + 4,004) + 3×(74)

6,400

3,163 + 222

6,400

3,385

6,400

= 0.5289 = 52.89 cM Incorrect distance =

½(2,322) + 3×(0)

6,400

1,161 + 0

6,400

1,161

6,400

= 0.1814 = 18.14 cM Incorrect distance =

½(74) + 3×(74)

6,400

37 + 222

6,400

259

6,400

= 0.0405 = 4.05 cM Incorrect distance =

½(2,322) + 3×(74)

6,400

1,161 + 222

6,400

1,383

6,400

= 0.2161 = 21.61 cM Correct distance =

½(0) + 3×(74)

6,400

0 + 222

6,400

222

6,400

= 0.0347 = 3.47 cM Incorrect MC

6045_5525

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is analogous to the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene Y is correlated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

658

520

TOTAL =

1,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and Y

distance =

½(658) + 3×(22)

1,200

329 + 66

1,200

395

1,200

= 0.3292 = 32.92 cM Incorrect distance =

½(0) + 3×(22)

1,200

0 + 66

1,200

= 0.0550 = 5.50 cM Incorrect distance =

½(520) + 3×(22)

1,200

260 + 66

1,200

326

1,200

= 0.2717 = 27.17 cM Correct distance =

½(22) + 3×(22)

1,200

11 + 66

1,200

= 0.0642 = 6.42 cM Incorrect distance =

½(22) + 3×(0)

1,200

11 + 0

1,200

= 0.0092 = 0.92 cM Incorrect distance =

½(658) + 3×(0)

1,200

329 + 0

1,200

329

1,200

= 0.2742 = 27.42 cM Incorrect MC

9aea_be13

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene J is analogous to the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.
Gene R is associated with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

2,046

3,079

TOTAL =

5,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes J and R

distance =

½(3,079) + 3×(75)

5,200

1539.5 + 225

5,200

1764.5

5,200

= 0.3393 = 33.93 cM Incorrect distance =

½(0) + 3×(75)

5,200

0 + 225

5,200

225

5,200

= 0.0433 = 4.33 cM Incorrect distance =

½(75) + 3×(75)

5,200

37.5 + 225

5,200

262.5

5,200

= 0.0505 = 5.05 cM Incorrect distance =

½(3,079) + 3×(0)

5,200

1539.5 + 0

5,200

1539.5

5,200

= 0.2961 = 29.61 cM Incorrect distance =

½(2,046) + 3×(75)

5,200

1,023 + 225

5,200

1,248

5,200

= 0.2400 = 24 cM Correct distance =

½(75) + 3×(0)

5,200

37.5 + 0

5,200

37.5

5,200

= 0.0072 = 0.72 cM Incorrect MC

f74e_9c3b

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is linked with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene P is correlated with the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

1,174

1,987

TOTAL =

3,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and P

distance =

½(1,174) + 3×(39)

3,200

587 + 117

3,200

704

3,200

= 0.2200 = 22 cM Correct distance =

½(1,987) + 3×(39)

3,200

993.5 + 117

3,200

1110.5

3,200

= 0.3470 = 34.70 cM Incorrect distance =

½(0) + 3×(39)

3,200

0 + 117

3,200

117

3,200

= 0.0366 = 3.66 cM Incorrect distance =

½(1,174) + 3×(0)

3,200

587 + 0

3,200

587

3,200

= 0.1834 = 18.34 cM Incorrect distance =

½(39) + 3×(39)

3,200

19.5 + 117

3,200

136.5

3,200

= 0.0427 = 4.27 cM Incorrect distance =

½(1,987) + 3×(0)

3,200

993.5 + 0

3,200

993.5

3,200

= 0.3105 = 31.05 cM Incorrect MC

324c_2992

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is related to the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene T is analogous to the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

2,536

3,975

TOTAL =

6,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and T

distance =

½(89) + 3×(89)

6,600

44.5 + 267

6,600

311.5

6,600

= 0.0472 = 4.72 cM Incorrect distance =

½(3,975) + 3×(0)

6,600

1987.5 + 0

6,600

1987.5

6,600

= 0.3011 = 30.11 cM Incorrect distance =

½(89) + 3×(0)

6,600

44.5 + 0

6,600

44.5

6,600

= 0.0067 = 0.67 cM Incorrect distance =

½(2,536) + 3×(89)

6,600

1,268 + 267

6,600

1,535

6,600

= 0.2326 = 23.26 cM Correct distance =

½(3,975) + 3×(89)

6,600

1987.5 + 267

6,600

2254.5

6,600

= 0.3416 = 34.16 cM Incorrect distance =

½(2,536 + 3,975) + 3×(89)

6,600

3255.5 + 267

6,600

3522.5

6,600

= 0.5337 = 53.37 cM Incorrect MC

91d9_45c3

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is linked with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene K is linked with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.

Set #

Tetrad Genotypes

Progeny
Count

1,582

2,154

TOTAL =

3,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and K

distance =

½(2,154) + 3×(0)

3,800

1,077 + 0

3,800

1,077

3,800

= 0.2834 = 28.34 cM Incorrect distance =

½(64) + 3×(64)

3,800

32 + 192

3,800

224

3,800

= 0.0589 = 5.89 cM Incorrect distance =

½(1,582) + 3×(0)

3,800

791 + 0

3,800

791

3,800

= 0.2082 = 20.82 cM Incorrect distance =

½(1,582) + 3×(64)

3,800

791 + 192

3,800

983

3,800

= 0.2587 = 25.87 cM Correct distance =

½(64) + 3×(0)

3,800

32 + 0

3,800

= 0.0084 = 0.84 cM Incorrect distance =

½(0) + 3×(64)

3,800

0 + 192

3,800

192

3,800

= 0.0505 = 5.05 cM Incorrect MC

8f03_0d5c

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is correlated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene E is analogous to the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.

Set #

Tetrad Genotypes

Progeny
Count

1,594

1,935

TOTAL =

3,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and E

distance =

½(1,935) + 3×(71)

3,600

967.5 + 213

3,600

1180.5

3,600

= 0.3279 = 32.79 cM Incorrect distance =

½(1,594) + 3×(71)

3,600

797 + 213

3,600

1,010

3,600

= 0.2806 = 28.06 cM Correct distance =

½(71) + 3×(71)

3,600

35.5 + 213

3,600

248.5

3,600

= 0.0690 = 6.90 cM Incorrect distance =

½(1,594 + 1,935) + 3×(71)

3,600

1764.5 + 213

3,600

1977.5

3,600

= 0.5493 = 54.93 cM Incorrect distance =

½(0) + 3×(71)

3,600

0 + 213

3,600

213

3,600

= 0.0592 = 5.92 cM Incorrect distance =

½(1,935) + 3×(0)

3,600

967.5 + 0

3,600

967.5

3,600

= 0.2687 = 26.88 cM Incorrect MC

2286_8fea

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is correlated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene N is connected with the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

222

4,506

4,872

TOTAL =

9,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and N

distance =

½(4,506) + 3×(222)

9,600

2,253 + 666

9,600

2,919

9,600

= 0.3041 = 30.41 cM Correct distance =

½(4,872) + 3×(0)

9,600

2,436 + 0

9,600

2,436

9,600

= 0.2537 = 25.37 cM Incorrect distance =

½(4,872) + 3×(222)

9,600

2,436 + 666

9,600

3,102

9,600

= 0.3231 = 32.31 cM Incorrect distance =

½(0) + 3×(222)

9,600

0 + 666

9,600

666

9,600

= 0.0694 = 6.94 cM Incorrect distance =

½(4,506 + 4,872) + 3×(222)

9,600

4,689 + 666

9,600

5,355

9,600

= 0.5578 = 55.78 cM Incorrect distance =

½(222) + 3×(222)

9,600

111 + 666

9,600

777

9,600

= 0.0809 = 8.09 cM Incorrect MC

bd4e_1796

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is affiliated with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene W is correlated with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

128

2,904

3,568

TOTAL =

6,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and W

distance =

½(2,904) + 3×(128)

6,600

1,452 + 384

6,600

1,836

6,600

= 0.2782 = 27.82 cM Correct distance =

½(0) + 3×(128)

6,600

0 + 384

6,600

384

6,600

= 0.0582 = 5.82 cM Incorrect distance =

½(3,568) + 3×(128)

6,600

1,784 + 384

6,600

2,168

6,600

= 0.3285 = 32.85 cM Incorrect distance =

½(3,568) + 3×(0)

6,600

1,784 + 0

6,600

1,784

6,600

= 0.2703 = 27.03 cM Incorrect distance =

½(128) + 3×(128)

6,600

64 + 384

6,600

448

6,600

= 0.0679 = 6.79 cM Incorrect distance =

½(128) + 3×(0)

6,600

64 + 0

6,600

= 0.0097 = 0.97 cM Incorrect MC

16e0_9ff6

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is correlated with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene X is related to the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

1,313

1,042

TOTAL =

2,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and X

distance =

½(1,042) + 3×(45)

2,400

521 + 135

2,400

656

2,400

= 0.2733 = 27.33 cM Correct distance =

½(0) + 3×(45)

2,400

0 + 135

2,400

135

2,400

= 0.0563 = 5.62 cM Incorrect distance =

½(1,313) + 3×(0)

2,400

656.5 + 0

2,400

656.5

2,400

= 0.2735 = 27.35 cM Incorrect distance =

½(1,313) + 3×(45)

2,400

656.5 + 135

2,400

791.5

2,400

= 0.3298 = 32.98 cM Incorrect distance =

½(45) + 3×(45)

2,400

22.5 + 135

2,400

157.5

2,400

= 0.0656 = 6.56 cM Incorrect distance =

½(1,042) + 3×(0)

2,400

521 + 0

2,400

521

2,400

= 0.2171 = 21.71 cM Incorrect MC

3331_410a

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene N is analogous to the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.
Gene P is analogous to the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

472

710

TOTAL =

1,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes N and P

distance =

½(18) + 3×(0)

1,200

9 + 0

1,200

= 0.0075 = 0.75 cM Incorrect distance =

½(710) + 3×(18)

1,200

355 + 54

1,200

409

1,200

= 0.3408 = 34.08 cM Incorrect distance =

½(18) + 3×(18)

1,200

9 + 54

1,200

= 0.0525 = 5.25 cM Incorrect distance =

½(472 + 710) + 3×(18)

1,200

591 + 54

1,200

645

1,200

= 0.5375 = 53.75 cM Incorrect distance =

½(472) + 3×(18)

1,200

236 + 54

1,200

290

1,200

= 0.2417 = 24.17 cM Correct distance =

½(0) + 3×(18)

1,200

0 + 54

1,200

= 0.0450 = 4.50 cM Incorrect MC

8872_2457

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is correlated with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene N is connected with the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

108

2,724

3,768

TOTAL =

6,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and N

distance =

½(3,768) + 3×(0)

6,600

1,884 + 0

6,600

1,884

6,600

= 0.2855 = 28.55 cM Incorrect distance =

½(2,724) + 3×(108)

6,600

1,362 + 324

6,600

1,686

6,600

= 0.2555 = 25.55 cM Correct distance =

½(108) + 3×(108)

6,600

54 + 324

6,600

378

6,600

= 0.0573 = 5.73 cM Incorrect distance =

½(3,768) + 3×(108)

6,600

1,884 + 324

6,600

2,208

6,600

= 0.3345 = 33.45 cM Incorrect distance =

½(2,724 + 3,768) + 3×(108)

6,600

3,246 + 324

6,600

3,570

6,600

= 0.5409 = 54.09 cM Incorrect distance =

½(0) + 3×(108)

6,600

0 + 324

6,600

324

6,600

= 0.0491 = 4.91 cM Incorrect MC

7035_8a9a

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is analogous to the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene P is analogous to the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

2,234

4,098

TOTAL =

6,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and P

distance =

½(2,234) + 3×(68)

6,400

1,117 + 204

6,400

1,321

6,400

= 0.2064 = 20.64 cM Correct distance =

½(4,098) + 3×(68)

6,400

2,049 + 204

6,400

2,253

6,400

= 0.3520 = 35.20 cM Incorrect distance =

½(0) + 3×(68)

6,400

0 + 204

6,400

204

6,400

= 0.0319 = 3.19 cM Incorrect distance =

½(2,234 + 4,098) + 3×(68)

6,400

3,166 + 204

6,400

3,370

6,400

= 0.5266 = 52.66 cM Incorrect distance =

½(2,234) + 3×(0)

6,400

1,117 + 0

6,400

1,117

6,400

= 0.1745 = 17.45 cM Incorrect distance =

½(68) + 3×(68)

6,400

34 + 204

6,400

238

6,400

= 0.0372 = 3.72 cM Incorrect MC

1942_4761

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is analogous to the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene F is correlated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.

Set #

Tetrad Genotypes

Progeny
Count

5,473

3,222

105

TOTAL =

8,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and F

distance =

½(0) + 3×(105)

8,800

0 + 315

8,800

315

8,800

= 0.0358 = 3.58 cM Incorrect distance =

½(5,473) + 3×(105)

8,800

2736.5 + 315

8,800

3051.5

8,800

= 0.3468 = 34.68 cM Incorrect distance =

½(105) + 3×(0)

8,800

52.5 + 0

8,800

52.5

8,800

= 0.0060 = 0.60 cM Incorrect distance =

½(3,222) + 3×(105)

8,800

1,611 + 315

8,800

1,926

8,800

= 0.2189 = 21.89 cM Correct distance =

½(5,473) + 3×(0)

8,800

2736.5 + 0

8,800

2736.5

8,800

= 0.3110 = 31.10 cM Incorrect distance =

½(3,222) + 3×(0)

8,800

1,611 + 0

8,800

1,611

8,800

= 0.1831 = 18.31 cM Incorrect MC

426b_2d90

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is correlated with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene M is linked with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

2,540

2,162

TOTAL =

4,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and M

distance =

½(2,162) + 3×(0)

4,800

1,081 + 0

4,800

1,081

4,800

= 0.2252 = 22.52 cM Incorrect distance =

½(2,162) + 3×(98)

4,800

1,081 + 294

4,800

1,375

4,800

= 0.2865 = 28.65 cM Correct distance =

½(2,540) + 3×(0)

4,800

1,270 + 0

4,800

1,270

4,800

= 0.2646 = 26.46 cM Incorrect distance =

½(2,540) + 3×(98)

4,800

1,270 + 294

4,800

1,564

4,800

= 0.3258 = 32.58 cM Incorrect distance =

½(98) + 3×(0)

4,800

49 + 0

4,800

= 0.0102 = 1.02 cM Incorrect distance =

½(98) + 3×(98)

4,800

49 + 294

4,800

343

4,800

= 0.0715 = 7.15 cM Incorrect MC

5f9e_1380

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene J is related to the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.
Gene W is related to the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

1,472

898

TOTAL =

2,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes J and W

distance =

½(898) + 3×(0)

2,400

449 + 0

2,400

449

2,400

= 0.1871 = 18.71 cM Incorrect distance =

½(898) + 3×(30)

2,400

449 + 90

2,400

539

2,400

= 0.2246 = 22.46 cM Correct distance =

½(0) + 3×(30)

2,400

0 + 90

2,400

= 0.0375 = 3.75 cM Incorrect distance =

½(1,472) + 3×(30)

2,400

736 + 90

2,400

826

2,400

= 0.3442 = 34.42 cM Incorrect distance =

½(30) + 3×(30)

2,400

15 + 90

2,400

105

2,400

= 0.0437 = 4.38 cM Incorrect distance =

½(1,472) + 3×(0)

2,400

736 + 0

2,400

736

2,400

= 0.3067 = 30.67 cM Incorrect MC

7790_b8d4

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is connected with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene E is connected with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.

Set #

Tetrad Genotypes

Progeny
Count

1,584

1,740

TOTAL =

3,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and E

distance =

½(1,584) + 3×(76)

3,400

792 + 228

3,400

1,020

3,400

= 0.3000 = 30 cM Correct distance =

½(1,740) + 3×(0)

3,400

870 + 0

3,400

870

3,400

= 0.2559 = 25.59 cM Incorrect distance =

½(1,584 + 1,740) + 3×(76)

3,400

1,662 + 228

3,400

1,890

3,400

= 0.5559 = 55.59 cM Incorrect distance =

½(76) + 3×(76)

3,400

38 + 228

3,400

266

3,400

= 0.0782 = 7.82 cM Incorrect distance =

½(1,584) + 3×(0)

3,400

792 + 0

3,400

792

3,400

= 0.2329 = 23.29 cM Incorrect distance =

½(1,740) + 3×(76)

3,400

870 + 228

3,400

1,098

3,400

= 0.3229 = 32.29 cM Incorrect MC

91d0_ede9

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is associated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene J is affiliated with the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.

Set #

Tetrad Genotypes

Progeny
Count

1,528

1,034

TOTAL =

2,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and J

distance =

½(1,034) + 3×(0)

2,600

517 + 0

2,600

517

2,600

= 0.1988 = 19.88 cM Incorrect distance =

½(38) + 3×(0)

2,600

19 + 0

2,600

= 0.0073 = 0.73 cM Incorrect distance =

½(1,528) + 3×(0)

2,600

764 + 0

2,600

764

2,600

= 0.2938 = 29.38 cM Incorrect distance =

½(1,528) + 3×(38)

2,600

764 + 114

2,600

878

2,600

= 0.3377 = 33.77 cM Incorrect distance =

½(1,034) + 3×(38)

2,600

517 + 114

2,600

631

2,600

= 0.2427 = 24.27 cM Correct distance =

½(38) + 3×(38)

2,600

19 + 114

2,600

133

2,600

= 0.0512 = 5.12 cM Incorrect MC

ba7b_03f3

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene M is connected with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.
Gene X is related to the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

171

3,648

4,181

TOTAL =

8,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes M and X

distance =

½(3,648 + 4,181) + 3×(171)

8,000

3914.5 + 513

8,000

4427.5

8,000

= 0.5534 = 55.34 cM Incorrect distance =

½(4,181) + 3×(171)

8,000

2090.5 + 513

8,000

2603.5

8,000

= 0.3254 = 32.54 cM Incorrect distance =

½(4,181) + 3×(0)

8,000

2090.5 + 0

8,000

2090.5

8,000

= 0.2613 = 26.13 cM Incorrect distance =

½(171) + 3×(0)

8,000

85.5 + 0

8,000

85.5

8,000

= 0.0107 = 1.07 cM Incorrect distance =

½(0) + 3×(171)

8,000

0 + 513

8,000

513

8,000

= 0.0641 = 6.41 cM Incorrect distance =

½(3,648) + 3×(171)

8,000

1,824 + 513

8,000

2,337

8,000

= 0.2921 = 29.21 cM Correct MC

6d2a_5ef5

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is correlated with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene N is associated with the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

629

360

TOTAL =

1,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and N

distance =

½(0) + 3×(11)

1,000

0 + 33

1,000

= 0.0330 = 3.30 cM Incorrect distance =

½(360) + 3×(11)

1,000

180 + 33

1,000

213

1,000

= 0.2130 = 21.30 cM Correct distance =

½(360) + 3×(0)

1,000

180 + 0

1,000

180

1,000

= 0.1800 = 18 cM Incorrect distance =

½(360 + 629) + 3×(11)

1,000

494.5 + 33

1,000

527.5

1,000

= 0.5275 = 52.75 cM Incorrect distance =

½(629) + 3×(0)

1,000

314.5 + 0

1,000

314.5

1,000

= 0.3145 = 31.45 cM Incorrect distance =

½(11) + 3×(0)

1,000

5.5 + 0

1,000

5.5

1,000

= 0.0055 = 0.55 cM Incorrect MC

c547_ba9a

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is linked with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene J is connected with the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.

Set #

Tetrad Genotypes

Progeny
Count

5,286

3,954

160

TOTAL =

9,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and J

distance =

½(3,954) + 3×(160)

9,400

1,977 + 480

9,400

2,457

9,400

= 0.2614 = 26.14 cM Correct distance =

½(3,954) + 3×(0)

9,400

1,977 + 0

9,400

1,977

9,400

= 0.2103 = 21.03 cM Incorrect distance =

½(3,954 + 5,286) + 3×(160)

9,400

4,620 + 480

9,400

5,100

9,400

= 0.5426 = 54.26 cM Incorrect distance =

½(5,286) + 3×(0)

9,400

2,643 + 0

9,400

2,643

9,400

= 0.2812 = 28.12 cM Incorrect distance =

½(5,286) + 3×(160)

9,400

2,643 + 480

9,400

3,123

9,400

= 0.3322 = 33.22 cM Incorrect distance =

½(0) + 3×(160)

9,400

0 + 480

9,400

480

9,400

= 0.0511 = 5.11 cM Incorrect MC

dccf_9189

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene H is affiliated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.
Gene W is affiliated with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

2,892

2,584

124

TOTAL =

5,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes H and W

distance =

½(2,892) + 3×(0)

5,600

1,446 + 0

5,600

1,446

5,600

= 0.2582 = 25.82 cM Incorrect distance =

½(124) + 3×(0)

5,600

62 + 0

5,600

= 0.0111 = 1.11 cM Incorrect distance =

½(2,584 + 2,892) + 3×(124)

5,600

2,738 + 372

5,600

3,110

5,600

= 0.5554 = 55.54 cM Incorrect distance =

½(2,584) + 3×(0)

5,600

1,292 + 0

5,600

1,292

5,600

= 0.2307 = 23.07 cM Incorrect distance =

½(2,584) + 3×(124)

5,600

1,292 + 372

5,600

1,664

5,600

= 0.2971 = 29.71 cM Correct distance =

½(2,892) + 3×(124)

5,600

1,446 + 372

5,600

1,818

5,600

= 0.3246 = 32.46 cM Incorrect MC

9603_3c18

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is connected with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene X is affiliated with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

4,998

3,656

146

TOTAL =

8,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and X

distance =

½(4,998) + 3×(146)

8,800

2,499 + 438

8,800

2,937

8,800

= 0.3337 = 33.38 cM Incorrect distance =

½(3,656) + 3×(146)

8,800

1,828 + 438

8,800

2,266

8,800

= 0.2575 = 25.75 cM Correct distance =

½(3,656 + 4,998) + 3×(146)

8,800

4,327 + 438

8,800

4,765

8,800

= 0.5415 = 54.15 cM Incorrect distance =

½(146) + 3×(0)

8,800

73 + 0

8,800

= 0.0083 = 0.83 cM Incorrect distance =

½(146) + 3×(146)

8,800

73 + 438

8,800

511

8,800

= 0.0581 = 5.81 cM Incorrect distance =

½(4,998) + 3×(0)

8,800

2,499 + 0

8,800

2,499

8,800

= 0.2840 = 28.40 cM Incorrect MC

70c7_00db

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is affiliated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene J is analogous to the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.

Set #

Tetrad Genotypes

Progeny
Count

4,549

3,690

161

TOTAL =

8,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and J

distance =

½(3,690) + 3×(161)

8,400

1,845 + 483

8,400

2,328

8,400

= 0.2771 = 27.71 cM Correct distance =

½(4,549) + 3×(161)

8,400

2274.5 + 483

8,400

2757.5

8,400

= 0.3283 = 32.83 cM Incorrect distance =

½(0) + 3×(161)

8,400

0 + 483

8,400

483

8,400

= 0.0575 = 5.75 cM Incorrect distance =

½(161) + 3×(161)

8,400

80.5 + 483

8,400

563.5

8,400

= 0.0671 = 6.71 cM Incorrect distance =

½(161) + 3×(0)

8,400

80.5 + 0

8,400

80.5

8,400

= 0.0096 = 0.96 cM Incorrect distance =

½(3,690) + 3×(0)

8,400

1,845 + 0

8,400

1,845

8,400

= 0.2196 = 21.96 cM Incorrect MC

2907_500a

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene N is related to the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.
Gene T is connected with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

1,138

1,014

TOTAL =

2,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes N and T

distance =

½(48) + 3×(48)

2,200

24 + 144

2,200

168

2,200

= 0.0764 = 7.64 cM Incorrect distance =

½(1,138) + 3×(48)

2,200

569 + 144

2,200

713

2,200

= 0.3241 = 32.41 cM Incorrect distance =

½(1,014) + 3×(0)

2,200

507 + 0

2,200

507

2,200

= 0.2305 = 23.05 cM Incorrect distance =

½(1,014) + 3×(48)

2,200

507 + 144

2,200

651

2,200

= 0.2959 = 29.59 cM Correct distance =

½(1,014 + 1,138) + 3×(48)

2,200

1,076 + 144

2,200

1,220

2,200

= 0.5545 = 55.45 cM Incorrect distance =

½(48) + 3×(0)

2,200

24 + 0

2,200

= 0.0109 = 1.09 cM Incorrect MC

d0f6_d553

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is related to the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene M is analogous to the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

1,134

1,827

TOTAL =

3,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and M

distance =

½(39) + 3×(39)

3,000

19.5 + 117

3,000

136.5

3,000

= 0.0455 = 4.55 cM Incorrect distance =

½(1,827) + 3×(0)

3,000

913.5 + 0

3,000

913.5

3,000

= 0.3045 = 30.45 cM Incorrect distance =

½(1,827) + 3×(39)

3,000

913.5 + 117

3,000

1030.5

3,000

= 0.3435 = 34.35 cM Incorrect distance =

½(1,134) + 3×(39)

3,000

567 + 117

3,000

684

3,000

= 0.2280 = 22.80 cM Correct distance =

½(39) + 3×(0)

3,000

19.5 + 0

3,000

19.5

3,000

= 0.0065 = 0.65 cM Incorrect distance =

½(0) + 3×(39)

3,000

0 + 117

3,000

117

3,000

= 0.0390 = 3.90 cM Incorrect MC

04e6_2d77

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is connected with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene H is correlated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

498

478

TOTAL =

1,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and H

distance =

½(24) + 3×(0)

1,000

12 + 0

1,000

= 0.0120 = 1.20 cM Incorrect distance =

½(478 + 498) + 3×(24)

1,000

488 + 72

1,000

560

1,000

= 0.5600 = 56 cM Incorrect distance =

½(478) + 3×(0)

1,000

239 + 0

1,000

239

1,000

= 0.2390 = 23.90 cM Incorrect distance =

½(0) + 3×(24)

1,000

0 + 72

1,000

= 0.0720 = 7.20 cM Incorrect distance =

½(478) + 3×(24)

1,000

239 + 72

1,000

311

1,000

= 0.3110 = 31.10 cM Correct distance =

½(498) + 3×(24)

1,000

249 + 72

1,000

321

1,000

= 0.3210 = 32.10 cM Incorrect MC

50f7_c206

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene H is related to the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.
Gene X is related to the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

3,969

2,728

103

TOTAL =

6,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes H and X

distance =

½(103) + 3×(0)

6,800

51.5 + 0

6,800

51.5

6,800

= 0.0076 = 0.76 cM Incorrect distance =

½(2,728) + 3×(103)

6,800

1,364 + 309

6,800

1,673

6,800

= 0.2460 = 24.60 cM Correct distance =

½(103) + 3×(103)

6,800

51.5 + 309

6,800

360.5

6,800

= 0.0530 = 5.30 cM Incorrect distance =

½(2,728 + 3,969) + 3×(103)

6,800

3348.5 + 309

6,800

3657.5

6,800

= 0.5379 = 53.79 cM Incorrect distance =

½(2,728) + 3×(0)

6,800

1,364 + 0

6,800

1,364

6,800

= 0.2006 = 20.06 cM Incorrect distance =

½(0) + 3×(103)

6,800

0 + 309

6,800

309

6,800

= 0.0454 = 4.54 cM Incorrect MC

8d48_45c8

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is associated with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene M is correlated with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

199

4,100

4,501

TOTAL =

8,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and M

distance =

½(199) + 3×(199)

8,800

99.5 + 597

8,800

696.5

8,800

= 0.0791 = 7.91 cM Incorrect distance =

½(4,100 + 4,501) + 3×(199)

8,800

4300.5 + 597

8,800

4897.5

8,800

= 0.5565 = 55.65 cM Incorrect distance =

½(0) + 3×(199)

8,800

0 + 597

8,800

597

8,800

= 0.0678 = 6.78 cM Incorrect distance =

½(4,100) + 3×(199)

8,800

2,050 + 597

8,800

2,647

8,800

= 0.3008 = 30.08 cM Correct distance =

½(4,501) + 3×(0)

8,800

2250.5 + 0

8,800

2250.5

8,800

= 0.2557 = 25.57 cM Incorrect distance =

½(4,501) + 3×(199)

8,800

2250.5 + 597

8,800

2847.5

8,800

= 0.3236 = 32.36 cM Incorrect MC

19ca_fdd8

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is analogous to the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene P is linked with the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

3,090

1,848

TOTAL =

5,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and P

distance =

½(1,848) + 3×(62)

5,000

924 + 186

5,000

1,110

5,000

= 0.2220 = 22.20 cM Correct distance =

½(1,848) + 3×(0)

5,000

924 + 0

5,000

924

5,000

= 0.1848 = 18.48 cM Incorrect distance =

½(62) + 3×(62)

5,000

31 + 186

5,000

217

5,000

= 0.0434 = 4.34 cM Incorrect distance =

½(3,090) + 3×(62)

5,000

1,545 + 186

5,000

1,731

5,000

= 0.3462 = 34.62 cM Incorrect distance =

½(62) + 3×(0)

5,000

31 + 0

5,000

= 0.0062 = 0.62 cM Incorrect distance =

½(0) + 3×(62)

5,000

0 + 186

5,000

186

5,000

= 0.0372 = 3.72 cM Incorrect MC

0a14_2be0

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is connected with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene T is associated with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

3,460

2,258

TOTAL =

5,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and T

distance =

½(3,460) + 3×(0)

5,800

1,730 + 0

5,800

1,730

5,800

= 0.2983 = 29.83 cM Incorrect distance =

½(2,258 + 3,460) + 3×(82)

5,800

2,859 + 246

5,800

3,105

5,800

= 0.5353 = 53.53 cM Incorrect distance =

½(82) + 3×(0)

5,800

41 + 0

5,800

= 0.0071 = 0.71 cM Incorrect distance =

½(0) + 3×(82)

5,800

0 + 246

5,800

246

5,800

= 0.0424 = 4.24 cM Incorrect distance =

½(2,258) + 3×(82)

5,800

1,129 + 246

5,800

1,375

5,800

= 0.2371 = 23.71 cM Correct distance =

½(3,460) + 3×(82)

5,800

1,730 + 246

5,800

1,976

5,800

= 0.3407 = 34.07 cM Incorrect MC

fe45_ee87

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is analogous to the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene J is linked with the 'jeweled' phenotype. A budding yeast that is homozygous recessive for Gene J colonies appear dotted with tiny, iridescent spots that sparkle under light.

Set #

Tetrad Genotypes

Progeny
Count

1,394

1,538

TOTAL =

3,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and J

distance =

½(1,394 + 1,538) + 3×(68)

3,000

1,466 + 204

3,000

1,670

3,000

= 0.5567 = 55.67 cM Incorrect distance =

½(1,394) + 3×(0)

3,000

697 + 0

3,000

697

3,000

= 0.2323 = 23.23 cM Incorrect distance =

½(1,538) + 3×(0)

3,000

769 + 0

3,000

769

3,000

= 0.2563 = 25.63 cM Incorrect distance =

½(0) + 3×(68)

3,000

0 + 204

3,000

204

3,000

= 0.0680 = 6.80 cM Incorrect distance =

½(1,394) + 3×(68)

3,000

697 + 204

3,000

901

3,000

= 0.3003 = 30.03 cM Correct distance =

½(68) + 3×(0)

3,000

34 + 0

3,000

= 0.0113 = 1.13 cM Incorrect MC

dd9c_3332

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is linked with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene R is connected with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

2,042

3,288

TOTAL =

5,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and R

distance =

½(70) + 3×(70)

5,400

35 + 210

5,400

245

5,400

= 0.0454 = 4.54 cM Incorrect distance =

½(0) + 3×(70)

5,400

0 + 210

5,400

210

5,400

= 0.0389 = 3.89 cM Incorrect distance =

½(3,288) + 3×(0)

5,400

1,644 + 0

5,400

1,644

5,400

= 0.3044 = 30.44 cM Incorrect distance =

½(2,042) + 3×(70)

5,400

1,021 + 210

5,400

1,231

5,400

= 0.2280 = 22.80 cM Correct distance =

½(70) + 3×(0)

5,400

35 + 0

5,400

= 0.0065 = 0.65 cM Incorrect distance =

½(3,288) + 3×(70)

5,400

1,644 + 210

5,400

1,854

5,400

= 0.3433 = 34.33 cM Incorrect MC

f0da_b13c

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is connected with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene C is related to the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.

Set #

Tetrad Genotypes

Progeny
Count

3,210

1,926

TOTAL =

5,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and C

distance =

½(3,210) + 3×(64)

5,200

1,605 + 192

5,200

1,797

5,200

= 0.3456 = 34.56 cM Incorrect distance =

½(64) + 3×(0)

5,200

32 + 0

5,200

= 0.0062 = 0.62 cM Incorrect distance =

½(3,210) + 3×(0)

5,200

1,605 + 0

5,200

1,605

5,200

= 0.3087 = 30.87 cM Incorrect distance =

½(0) + 3×(64)

5,200

0 + 192

5,200

192

5,200

= 0.0369 = 3.69 cM Incorrect distance =

½(1,926 + 3,210) + 3×(64)

5,200

2,568 + 192

5,200

2,760

5,200

= 0.5308 = 53.08 cM Incorrect distance =

½(1,926) + 3×(64)

5,200

963 + 192

5,200

1,155

5,200

= 0.2221 = 22.21 cM Correct MC

3ad3_39e9

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is correlated with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene F is analogous to the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.

Set #

Tetrad Genotypes

Progeny
Count

173

4,068

5,159

TOTAL =

9,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and F

distance =

½(173) + 3×(173)

9,400

86.5 + 519

9,400

605.5

9,400

= 0.0644 = 6.44 cM Incorrect distance =

½(5,159) + 3×(0)

9,400

2579.5 + 0

9,400

2579.5

9,400

= 0.2744 = 27.44 cM Incorrect distance =

½(173) + 3×(0)

9,400

86.5 + 0

9,400

86.5

9,400

= 0.0092 = 0.92 cM Incorrect distance =

½(4,068) + 3×(173)

9,400

2,034 + 519

9,400

2,553

9,400

= 0.2716 = 27.16 cM Correct distance =

½(4,068) + 3×(0)

9,400

2,034 + 0

9,400

2,034

9,400

= 0.2164 = 21.64 cM Incorrect distance =

½(5,159) + 3×(173)

9,400

2579.5 + 519

9,400

3098.5

9,400

= 0.3296 = 32.96 cM Incorrect MC

0fcb_7297

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is linked with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene X is associated with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

4,599

4,562

239

TOTAL =

9,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and X

distance =

½(4,599) + 3×(239)

9,400

2299.5 + 717

9,400

3016.5

9,400

= 0.3209 = 32.09 cM Incorrect distance =

½(4,562) + 3×(239)

9,400

2,281 + 717

9,400

2,998

9,400

= 0.3189 = 31.89 cM Correct distance =

½(239) + 3×(239)

9,400

119.5 + 717

9,400

836.5

9,400

= 0.0890 = 8.90 cM Incorrect distance =

½(4,562) + 3×(0)

9,400

2,281 + 0

9,400

2,281

9,400

= 0.2427 = 24.27 cM Incorrect distance =

½(4,562 + 4,599) + 3×(239)

9,400

4580.5 + 717

9,400

5297.5

9,400

= 0.5636 = 56.36 cM Incorrect distance =

½(4,599) + 3×(0)

9,400

2299.5 + 0

9,400

2299.5

9,400

= 0.2446 = 24.46 cM Incorrect MC

1be9_f0a4

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is correlated with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene Y is affiliated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

5,120

2,794

TOTAL =

8,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and Y

distance =

½(2,794 + 5,120) + 3×(86)

8,000

3,957 + 258

8,000

4,215

8,000

= 0.5269 = 52.69 cM Incorrect distance =

½(0) + 3×(86)

8,000

0 + 258

8,000

258

8,000

= 0.0323 = 3.23 cM Incorrect distance =

½(2,794) + 3×(0)

8,000

1,397 + 0

8,000

1,397

8,000

= 0.1746 = 17.46 cM Incorrect distance =

½(2,794) + 3×(86)

8,000

1,397 + 258

8,000

1,655

8,000

= 0.2069 = 20.69 cM Correct distance =

½(86) + 3×(86)

8,000

43 + 258

8,000

301

8,000

= 0.0376 = 3.76 cM Incorrect distance =

½(86) + 3×(0)

8,000

43 + 0

8,000

= 0.0054 = 0.54 cM Incorrect MC

d73e_a5a3

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is analogous to the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene T is related to the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

1,944

2,986

TOTAL =

5,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and T

distance =

½(1,944) + 3×(70)

5,000

972 + 210

5,000

1,182

5,000

= 0.2364 = 23.64 cM Correct distance =

½(2,986) + 3×(70)

5,000

1,493 + 210

5,000

1,703

5,000

= 0.3406 = 34.06 cM Incorrect distance =

½(70) + 3×(70)

5,000

35 + 210

5,000

245

5,000

= 0.0490 = 4.90 cM Incorrect distance =

½(0) + 3×(70)

5,000

0 + 210

5,000

210

5,000

= 0.0420 = 4.20 cM Incorrect distance =

½(1,944) + 3×(0)

5,000

972 + 0

5,000

972

5,000

= 0.1944 = 19.44 cM Incorrect distance =

½(1,944 + 2,986) + 3×(70)

5,000

2,465 + 210

5,000

2,675

5,000

= 0.5350 = 53.50 cM Incorrect MC

7826_2ce6

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is connected with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene E is affiliated with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.

Set #

Tetrad Genotypes

Progeny
Count

2,263

2,222

115

TOTAL =

4,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and E

distance =

½(2,263) + 3×(115)

4,600

1131.5 + 345

4,600

1476.5

4,600

= 0.3210 = 32.10 cM Incorrect distance =

½(2,222 + 2,263) + 3×(115)

4,600

2242.5 + 345

4,600

2587.5

4,600

= 0.5625 = 56.25 cM Incorrect distance =

½(2,263) + 3×(0)

4,600

1131.5 + 0

4,600

1131.5

4,600

= 0.2460 = 24.60 cM Incorrect distance =

½(0) + 3×(115)

4,600

0 + 345

4,600

345

4,600

= 0.0750 = 7.50 cM Incorrect distance =

½(2,222) + 3×(115)

4,600

1,111 + 345

4,600

1,456

4,600

= 0.3165 = 31.65 cM Correct distance =

½(115) + 3×(0)

4,600

57.5 + 0

4,600

57.5

4,600

= 0.0125 = 1.25 cM Incorrect MC

554a_be14

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is associated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene B is analogous to the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.

Set #

Tetrad Genotypes

Progeny
Count

6,044

3,446

110

TOTAL =

9,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and B

distance =

½(6,044) + 3×(110)

9,600

3,022 + 330

9,600

3,352

9,600

= 0.3492 = 34.92 cM Incorrect distance =

½(3,446) + 3×(110)

9,600

1,723 + 330

9,600

2,053

9,600

= 0.2139 = 21.39 cM Correct distance =

½(0) + 3×(110)

9,600

0 + 330

9,600

330

9,600

= 0.0344 = 3.44 cM Incorrect distance =

½(3,446) + 3×(0)

9,600

1,723 + 0

9,600

1,723

9,600

= 0.1795 = 17.95 cM Incorrect distance =

½(3,446 + 6,044) + 3×(110)

9,600

4,745 + 330

9,600

5,075

9,600

= 0.5286 = 52.86 cM Incorrect distance =

½(110) + 3×(110)

9,600

55 + 330

9,600

385

9,600

= 0.0401 = 4.01 cM Incorrect MC

8571_4c7b

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene T is analogous to the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.
Gene W is related to the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

2,523

1,432

TOTAL =

4,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes T and W

distance =

½(45) + 3×(45)

4,000

22.5 + 135

4,000

157.5

4,000

= 0.0394 = 3.94 cM Incorrect distance =

½(2,523) + 3×(0)

4,000

1261.5 + 0

4,000

1261.5

4,000

= 0.3154 = 31.54 cM Incorrect distance =

½(0) + 3×(45)

4,000

0 + 135

4,000

135

4,000

= 0.0338 = 3.38 cM Incorrect distance =

½(2,523) + 3×(45)

4,000

1261.5 + 135

4,000

1396.5

4,000

= 0.3491 = 34.91 cM Incorrect distance =

½(1,432) + 3×(45)

4,000

716 + 135

4,000

851

4,000

= 0.2127 = 21.27 cM Correct distance =

½(1,432 + 2,523) + 3×(45)

4,000

1977.5 + 135

4,000

2112.5

4,000

= 0.5281 = 52.81 cM Incorrect MC

d82c_497a

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is linked with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene F is affiliated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.

Set #

Tetrad Genotypes

Progeny
Count

5,181

4,048

171

TOTAL =

9,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and F

distance =

½(4,048 + 5,181) + 3×(171)

9,400

4614.5 + 513

9,400

5127.5

9,400

= 0.5455 = 54.55 cM Incorrect distance =

½(4,048) + 3×(0)

9,400

2,024 + 0

9,400

2,024

9,400

= 0.2153 = 21.53 cM Incorrect distance =

½(4,048) + 3×(171)

9,400

2,024 + 513

9,400

2,537

9,400

= 0.2699 = 26.99 cM Correct distance =

½(0) + 3×(171)

9,400

0 + 513

9,400

513

9,400

= 0.0546 = 5.46 cM Incorrect distance =

½(5,181) + 3×(0)

9,400

2590.5 + 0

9,400

2590.5

9,400

= 0.2756 = 27.56 cM Incorrect distance =

½(171) + 3×(0)

9,400

85.5 + 0

9,400

85.5

9,400

= 0.0091 = 0.91 cM Incorrect MC

5b93_0e9f

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is associated with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene C is connected with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.

Set #

Tetrad Genotypes

Progeny
Count

4,273

3,934

193

TOTAL =

8,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and C

distance =

½(4,273) + 3×(0)

8,400

2136.5 + 0

8,400

2136.5

8,400

= 0.2543 = 25.43 cM Incorrect distance =

½(0) + 3×(193)

8,400

0 + 579

8,400

579

8,400

= 0.0689 = 6.89 cM Incorrect distance =

½(193) + 3×(0)

8,400

96.5 + 0

8,400

96.5

8,400

= 0.0115 = 1.15 cM Incorrect distance =

½(3,934) + 3×(193)

8,400

1,967 + 579

8,400

2,546

8,400

= 0.3031 = 30.31 cM Correct distance =

½(193) + 3×(193)

8,400

96.5 + 579

8,400

675.5

8,400

= 0.0804 = 8.04 cM Incorrect distance =

½(3,934) + 3×(0)

8,400

1,967 + 0

8,400

1,967

8,400

= 0.2342 = 23.42 cM Incorrect MC

dce0_cb9c

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene T is analogous to the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.
Gene X is related to the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

2,787

1,752

TOTAL =

4,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes T and X

distance =

½(2,787) + 3×(61)

4,600

1393.5 + 183

4,600

1576.5

4,600

= 0.3427 = 34.27 cM Incorrect distance =

½(1,752) + 3×(61)

4,600

876 + 183

4,600

1,059

4,600

= 0.2302 = 23.02 cM Correct distance =

½(1,752) + 3×(0)

4,600

876 + 0

4,600

876

4,600

= 0.1904 = 19.04 cM Incorrect distance =

½(1,752 + 2,787) + 3×(61)

4,600

2269.5 + 183

4,600

2452.5

4,600

= 0.5332 = 53.32 cM Incorrect distance =

½(61) + 3×(0)

4,600

30.5 + 0

4,600

30.5

4,600

= 0.0066 = 0.66 cM Incorrect distance =

½(61) + 3×(61)

4,600

30.5 + 183

4,600

213.5

4,600

= 0.0464 = 4.64 cM Incorrect MC

6604_ef1b

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene M is affiliated with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.
Gene W is correlated with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

128

2,736

3,136

TOTAL =

6,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes M and W

distance =

½(128) + 3×(0)

6,000

64 + 0

6,000

= 0.0107 = 1.07 cM Incorrect distance =

½(0) + 3×(128)

6,000

0 + 384

6,000

384

6,000

= 0.0640 = 6.40 cM Incorrect distance =

½(128) + 3×(128)

6,000

64 + 384

6,000

448

6,000

= 0.0747 = 7.47 cM Incorrect distance =

½(2,736 + 3,136) + 3×(128)

6,000

2,936 + 384

6,000

3,320

6,000

= 0.5533 = 55.33 cM Incorrect distance =

½(3,136) + 3×(128)

6,000

1,568 + 384

6,000

1,952

6,000

= 0.3253 = 32.53 cM Incorrect distance =

½(2,736) + 3×(128)

6,000

1,368 + 384

6,000

1,752

6,000

= 0.2920 = 29.20 cM Correct MC

5028_0835

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is associated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene Y is linked with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

3,543

2,556

101

TOTAL =

6,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and Y

distance =

½(101) + 3×(0)

6,200

50.5 + 0

6,200

50.5

6,200

= 0.0081 = 0.81 cM Incorrect distance =

½(3,543) + 3×(101)

6,200

1771.5 + 303

6,200

2074.5

6,200

= 0.3346 = 33.46 cM Incorrect distance =

½(3,543) + 3×(0)

6,200

1771.5 + 0

6,200

1771.5

6,200

= 0.2857 = 28.57 cM Incorrect distance =

½(2,556) + 3×(101)

6,200

1,278 + 303

6,200

1,581

6,200

= 0.2550 = 25.50 cM Correct distance =

½(101) + 3×(101)

6,200

50.5 + 303

6,200

353.5

6,200

= 0.0570 = 5.70 cM Incorrect distance =

½(2,556 + 3,543) + 3×(101)

6,200

3049.5 + 303

6,200

3352.5

6,200

= 0.5407 = 54.07 cM Incorrect MC

8915_7d92

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is related to the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene C is related to the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.

Set #

Tetrad Genotypes

Progeny
Count

1,198

1,346

TOTAL =

2,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and C

distance =

½(56) + 3×(56)

2,600

28 + 168

2,600

196

2,600

= 0.0754 = 7.54 cM Incorrect distance =

½(0) + 3×(56)

2,600

0 + 168

2,600

168

2,600

= 0.0646 = 6.46 cM Incorrect distance =

½(1,198 + 1,346) + 3×(56)

2,600

1,272 + 168

2,600

1,440

2,600

= 0.5538 = 55.38 cM Incorrect distance =

½(1,198) + 3×(0)

2,600

599 + 0

2,600

599

2,600

= 0.2304 = 23.04 cM Incorrect distance =

½(1,346) + 3×(0)

2,600

673 + 0

2,600

673

2,600

= 0.2588 = 25.88 cM Incorrect distance =

½(1,198) + 3×(56)

2,600

599 + 168

2,600

767

2,600

= 0.2950 = 29.50 cM Correct MC

4c29_940b

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is correlated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene H is correlated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

1,752

3,194

TOTAL =

5,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and H

distance =

½(1,752 + 3,194) + 3×(54)

5,000

2,473 + 162

5,000

2,635

5,000

= 0.5270 = 52.70 cM Incorrect distance =

½(0) + 3×(54)

5,000

0 + 162

5,000

162

5,000

= 0.0324 = 3.24 cM Incorrect distance =

½(3,194) + 3×(0)

5,000

1,597 + 0

5,000

1,597

5,000

= 0.3194 = 31.94 cM Incorrect distance =

½(1,752) + 3×(0)

5,000

876 + 0

5,000

876

5,000

= 0.1752 = 17.52 cM Incorrect distance =

½(1,752) + 3×(54)

5,000

876 + 162

5,000

1,038

5,000

= 0.2076 = 20.76 cM Correct distance =

½(54) + 3×(0)

5,000

27 + 0

5,000

= 0.0054 = 0.54 cM Incorrect MC

8a11_2cfe

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is correlated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene N is analogous to the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

2,221

1,708

TOTAL =

4,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and N

distance =

½(2,221) + 3×(0)

4,000

1110.5 + 0

4,000

1110.5

4,000

= 0.2776 = 27.76 cM Incorrect distance =

½(0) + 3×(71)

4,000

0 + 213

4,000

213

4,000

= 0.0532 = 5.33 cM Incorrect distance =

½(1,708 + 2,221) + 3×(71)

4,000

1964.5 + 213

4,000

2177.5

4,000

= 0.5444 = 54.44 cM Incorrect distance =

½(2,221) + 3×(71)

4,000

1110.5 + 213

4,000

1323.5

4,000

= 0.3309 = 33.09 cM Incorrect distance =

½(1,708) + 3×(71)

4,000

854 + 213

4,000

1,067

4,000

= 0.2667 = 26.67 cM Correct distance =

½(71) + 3×(71)

4,000

35.5 + 213

4,000

248.5

4,000

= 0.0621 = 6.21 cM Incorrect MC

5076_da4c

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is correlated with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene X is correlated with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

1,792

2,744

TOTAL =

4,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and X

distance =

½(1,792) + 3×(0)

4,600

896 + 0

4,600

896

4,600

= 0.1948 = 19.48 cM Incorrect distance =

½(2,744) + 3×(64)

4,600

1,372 + 192

4,600

1,564

4,600

= 0.3400 = 34 cM Incorrect distance =

½(64) + 3×(64)

4,600

32 + 192

4,600

224

4,600

= 0.0487 = 4.87 cM Incorrect distance =

½(2,744) + 3×(0)

4,600

1,372 + 0

4,600

1,372

4,600

= 0.2983 = 29.83 cM Incorrect distance =

½(1,792) + 3×(64)

4,600

896 + 192

4,600

1,088

4,600

= 0.2365 = 23.65 cM Correct distance =

½(64) + 3×(0)

4,600

32 + 0

4,600

= 0.0070 = 0.70 cM Incorrect MC

bb39_0ea4

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is connected with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene R is associated with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

1,398

778

TOTAL =

2,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and R

distance =

½(24) + 3×(0)

2,200

12 + 0

2,200

= 0.0055 = 0.55 cM Incorrect distance =

½(24) + 3×(24)

2,200

12 + 72

2,200

= 0.0382 = 3.82 cM Incorrect distance =

½(1,398) + 3×(0)

2,200

699 + 0

2,200

699

2,200

= 0.3177 = 31.77 cM Incorrect distance =

½(1,398) + 3×(24)

2,200

699 + 72

2,200

771

2,200

= 0.3505 = 35.05 cM Incorrect distance =

½(778) + 3×(24)

2,200

389 + 72

2,200

461

2,200

= 0.2095 = 20.95 cM Correct distance =

½(0) + 3×(24)

2,200

0 + 72

2,200

= 0.0327 = 3.27 cM Incorrect MC

684d_6291

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is connected with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene Y is connected with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

128

3,272

4,600

TOTAL =

8,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and Y

distance =

½(3,272) + 3×(0)

8,000

1,636 + 0

8,000

1,636

8,000

= 0.2045 = 20.45 cM Incorrect distance =

½(4,600) + 3×(0)

8,000

2,300 + 0

8,000

2,300

8,000

= 0.2875 = 28.75 cM Incorrect distance =

½(3,272) + 3×(128)

8,000

1,636 + 384

8,000

2,020

8,000

= 0.2525 = 25.25 cM Correct distance =

½(0) + 3×(128)

8,000

0 + 384

8,000

384

8,000

= 0.0480 = 4.80 cM Incorrect distance =

½(4,600) + 3×(128)

8,000

2,300 + 384

8,000

2,684

8,000

= 0.3355 = 33.55 cM Incorrect distance =

½(3,272 + 4,600) + 3×(128)

8,000

3,936 + 384

8,000

4,320

8,000

= 0.5400 = 54 cM Incorrect MC

07e4_334e

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is related to the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene P is correlated with the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

1,968

1,192

TOTAL =

3,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and P

distance =

½(1,968) + 3×(0)

3,200

984 + 0

3,200

984

3,200

= 0.3075 = 30.75 cM Incorrect distance =

½(1,192) + 3×(0)

3,200

596 + 0

3,200

596

3,200

= 0.1862 = 18.62 cM Incorrect distance =

½(1,192) + 3×(40)

3,200

596 + 120

3,200

716

3,200

= 0.2238 = 22.38 cM Correct distance =

½(40) + 3×(0)

3,200

20 + 0

3,200

= 0.0063 = 0.62 cM Incorrect distance =

½(0) + 3×(40)

3,200

0 + 120

3,200

120

3,200

= 0.0375 = 3.75 cM Incorrect distance =

½(1,968) + 3×(40)

3,200

984 + 120

3,200

1,104

3,200

= 0.3450 = 34.50 cM Incorrect MC

8d4a_dc53

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is associated with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene X is associated with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

1,674

1,274

TOTAL =

3,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and X

distance =

½(1,674) + 3×(52)

3,000

837 + 156

3,000

993

3,000

= 0.3310 = 33.10 cM Incorrect distance =

½(52) + 3×(52)

3,000

26 + 156

3,000

182

3,000

= 0.0607 = 6.07 cM Incorrect distance =

½(0) + 3×(52)

3,000

0 + 156

3,000

156

3,000

= 0.0520 = 5.20 cM Incorrect distance =

½(1,274) + 3×(52)

3,000

637 + 156

3,000

793

3,000

= 0.2643 = 26.43 cM Correct distance =

½(1,274 + 1,674) + 3×(52)

3,000

1,474 + 156

3,000

1,630

3,000

= 0.5433 = 54.33 cM Incorrect distance =

½(52) + 3×(0)

3,000

26 + 0

3,000

= 0.0087 = 0.87 cM Incorrect MC

fe18_80da

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene R is related to the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.
Gene W is related to the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

1,720

1,792

TOTAL =

3,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes R and W

distance =

½(88) + 3×(0)

3,600

44 + 0

3,600

= 0.0122 = 1.22 cM Incorrect distance =

½(0) + 3×(88)

3,600

0 + 264

3,600

264

3,600

= 0.0733 = 7.33 cM Incorrect distance =

½(1,720) + 3×(88)

3,600

860 + 264

3,600

1,124

3,600

= 0.3122 = 31.22 cM Correct distance =

½(1,792) + 3×(0)

3,600

896 + 0

3,600

896

3,600

= 0.2489 = 24.89 cM Incorrect distance =

½(88) + 3×(88)

3,600

44 + 264

3,600

308

3,600

= 0.0856 = 8.56 cM Incorrect distance =

½(1,720 + 1,792) + 3×(88)

3,600

1,756 + 264

3,600

2,020

3,600

= 0.5611 = 56.11 cM Incorrect MC

914a_0efd

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is correlated with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene F is associated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.

Set #

Tetrad Genotypes

Progeny
Count

2,685

2,032

TOTAL =

4,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and F

distance =

½(2,032) + 3×(0)

4,800

1,016 + 0

4,800

1,016

4,800

= 0.2117 = 21.17 cM Incorrect distance =

½(0) + 3×(83)

4,800

0 + 249

4,800

249

4,800

= 0.0519 = 5.19 cM Incorrect distance =

½(2,032) + 3×(83)

4,800

1,016 + 249

4,800

1,265

4,800

= 0.2635 = 26.35 cM Correct distance =

½(2,032 + 2,685) + 3×(83)

4,800

2358.5 + 249

4,800

2607.5

4,800

= 0.5432 = 54.32 cM Incorrect distance =

½(83) + 3×(83)

4,800

41.5 + 249

4,800

290.5

4,800

= 0.0605 = 6.05 cM Incorrect distance =

½(2,685) + 3×(0)

4,800

1342.5 + 0

4,800

1342.5

4,800

= 0.2797 = 27.97 cM Incorrect MC

0512_f961

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is associated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene P is affiliated with the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

4,674

3,018

108

TOTAL =

7,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and P

distance =

½(3,018) + 3×(0)

7,800

1,509 + 0

7,800

1,509

7,800

= 0.1935 = 19.35 cM Incorrect distance =

½(3,018 + 4,674) + 3×(108)

7,800

3,846 + 324

7,800

4,170

7,800

= 0.5346 = 53.46 cM Incorrect distance =

½(108) + 3×(108)

7,800

54 + 324

7,800

378

7,800

= 0.0485 = 4.85 cM Incorrect distance =

½(3,018) + 3×(108)

7,800

1,509 + 324

7,800

1,833

7,800

= 0.2350 = 23.50 cM Correct distance =

½(4,674) + 3×(0)

7,800

2,337 + 0

7,800

2,337

7,800

= 0.2996 = 29.96 cM Incorrect distance =

½(0) + 3×(108)

7,800

0 + 324

7,800

324

7,800

= 0.0415 = 4.15 cM Incorrect MC

714c_404f

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is analogous to the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene K is connected with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.

Set #

Tetrad Genotypes

Progeny
Count

1,424

1,919

TOTAL =

3,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and K

distance =

½(1,424) + 3×(0)

3,400

712 + 0

3,400

712

3,400

= 0.2094 = 20.94 cM Incorrect distance =

½(1,424) + 3×(57)

3,400

712 + 171

3,400

883

3,400

= 0.2597 = 25.97 cM Correct distance =

½(1,424 + 1,919) + 3×(57)

3,400

1671.5 + 171

3,400

1842.5

3,400

= 0.5419 = 54.19 cM Incorrect distance =

½(0) + 3×(57)

3,400

0 + 171

3,400

171

3,400

= 0.0503 = 5.03 cM Incorrect distance =

½(1,919) + 3×(0)

3,400

959.5 + 0

3,400

959.5

3,400

= 0.2822 = 28.22 cM Incorrect distance =

½(57) + 3×(0)

3,400

28.5 + 0

3,400

28.5

3,400

= 0.0084 = 0.84 cM Incorrect MC

bb5e_68e6

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is connected with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene Y is associated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

2,752

2,524

124

TOTAL =

5,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and Y

distance =

½(0) + 3×(124)

5,400

0 + 372

5,400

372

5,400

= 0.0689 = 6.89 cM Incorrect distance =

½(124) + 3×(0)

5,400

62 + 0

5,400

= 0.0115 = 1.15 cM Incorrect distance =

½(2,524 + 2,752) + 3×(124)

5,400

2,638 + 372

5,400

3,010

5,400

= 0.5574 = 55.74 cM Incorrect distance =

½(2,752) + 3×(0)

5,400

1,376 + 0

5,400

1,376

5,400

= 0.2548 = 25.48 cM Incorrect distance =

½(2,524) + 3×(124)

5,400

1,262 + 372

5,400

1,634

5,400

= 0.3026 = 30.26 cM Correct distance =

½(124) + 3×(124)

5,400

62 + 372

5,400

434

5,400

= 0.0804 = 8.04 cM Incorrect MC

3bd4_8b91

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is associated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene H is linked with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

1,968

1,750

TOTAL =

3,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and H

distance =

½(82) + 3×(0)

3,800

41 + 0

3,800

= 0.0108 = 1.08 cM Incorrect distance =

½(1,750) + 3×(82)

3,800

875 + 246

3,800

1,121

3,800

= 0.2950 = 29.50 cM Correct distance =

½(1,968) + 3×(82)

3,800

984 + 246

3,800

1,230

3,800

= 0.3237 = 32.37 cM Incorrect distance =

½(0) + 3×(82)

3,800

0 + 246

3,800

246

3,800

= 0.0647 = 6.47 cM Incorrect distance =

½(1,750) + 3×(0)

3,800

875 + 0

3,800

875

3,800

= 0.2303 = 23.03 cM Incorrect distance =

½(1,968) + 3×(0)

3,800

984 + 0

3,800

984

3,800

= 0.2589 = 25.89 cM Incorrect MC

dd71_edcf

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is analogous to the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene R is correlated with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

3,301

2,774

125

TOTAL =

6,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and R

distance =

½(2,774) + 3×(0)

6,200

1,387 + 0

6,200

1,387

6,200

= 0.2237 = 22.37 cM Incorrect distance =

½(3,301) + 3×(0)

6,200

1650.5 + 0

6,200

1650.5

6,200

= 0.2662 = 26.62 cM Incorrect distance =

½(125) + 3×(0)

6,200

62.5 + 0

6,200

62.5

6,200

= 0.0101 = 1.01 cM Incorrect distance =

½(0) + 3×(125)

6,200

0 + 375

6,200

375

6,200

= 0.0605 = 6.05 cM Incorrect distance =

½(2,774 + 3,301) + 3×(125)

6,200

3037.5 + 375

6,200

3412.5

6,200

= 0.5504 = 55.04 cM Incorrect distance =

½(2,774) + 3×(125)

6,200

1,387 + 375

6,200

1,762

6,200

= 0.2842 = 28.42 cM Correct MC

33dc_ecb4

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene H is connected with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.
Gene R is associated with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

116

2,222

2,262

TOTAL =

4,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes H and R

distance =

½(2,222) + 3×(0)

4,600

1,111 + 0

4,600

1,111

4,600

= 0.2415 = 24.15 cM Incorrect distance =

½(2,222) + 3×(116)

4,600

1,111 + 348

4,600

1,459

4,600

= 0.3172 = 31.72 cM Correct distance =

½(116) + 3×(116)

4,600

58 + 348

4,600

406

4,600

= 0.0883 = 8.83 cM Incorrect distance =

½(2,262) + 3×(0)

4,600

1,131 + 0

4,600

1,131

4,600

= 0.2459 = 24.59 cM Incorrect distance =

½(116) + 3×(0)

4,600

58 + 0

4,600

= 0.0126 = 1.26 cM Incorrect distance =

½(0) + 3×(116)

4,600

0 + 348

4,600

348

4,600

= 0.0757 = 7.57 cM Incorrect MC

42e3_4e16

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene M is analogous to the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.
Gene T is connected with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

2,822

2,094

TOTAL =

5,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes M and T

distance =

½(2,094) + 3×(0)

5,000

1,047 + 0

5,000

1,047

5,000

= 0.2094 = 20.94 cM Incorrect distance =

½(2,822) + 3×(0)

5,000

1,411 + 0

5,000

1,411

5,000

= 0.2822 = 28.22 cM Incorrect distance =

½(84) + 3×(84)

5,000

42 + 252

5,000

294

5,000

= 0.0588 = 5.88 cM Incorrect distance =

½(0) + 3×(84)

5,000

0 + 252

5,000

252

5,000

= 0.0504 = 5.04 cM Incorrect distance =

½(2,094) + 3×(84)

5,000

1,047 + 252

5,000

1,299

5,000

= 0.2598 = 25.98 cM Correct distance =

½(84) + 3×(0)

5,000

42 + 0

5,000

= 0.0084 = 0.84 cM Incorrect MC

5c32_7423

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is correlated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene X is affiliated with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

180

3,894

4,526

TOTAL =

8,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and X

distance =

½(3,894) + 3×(0)

8,600

1,947 + 0

8,600

1,947

8,600

= 0.2264 = 22.64 cM Incorrect distance =

½(0) + 3×(180)

8,600

0 + 540

8,600

540

8,600

= 0.0628 = 6.28 cM Incorrect distance =

½(3,894) + 3×(180)

8,600

1,947 + 540

8,600

2,487

8,600

= 0.2892 = 28.92 cM Correct distance =

½(180) + 3×(180)

8,600

90 + 540

8,600

630

8,600

= 0.0733 = 7.33 cM Incorrect distance =

½(3,894 + 4,526) + 3×(180)

8,600

4,210 + 540

8,600

4,750

8,600

= 0.5523 = 55.23 cM Incorrect distance =

½(4,526) + 3×(0)

8,600

2,263 + 0

8,600

2,263

8,600

= 0.2631 = 26.31 cM Incorrect MC

3071_9c4e

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is linked with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene Y is affiliated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

1,412

1,726

TOTAL =

3,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and Y

distance =

½(1,726) + 3×(62)

3,200

863 + 186

3,200

1,049

3,200

= 0.3278 = 32.78 cM Incorrect distance =

½(62) + 3×(62)

3,200

31 + 186

3,200

217

3,200

= 0.0678 = 6.78 cM Incorrect distance =

½(62) + 3×(0)

3,200

31 + 0

3,200

= 0.0097 = 0.97 cM Incorrect distance =

½(1,412) + 3×(0)

3,200

706 + 0

3,200

706

3,200

= 0.2206 = 22.06 cM Incorrect distance =

½(1,412) + 3×(62)

3,200

706 + 186

3,200

892

3,200

= 0.2787 = 27.88 cM Correct distance =

½(0) + 3×(62)

3,200

0 + 186

3,200

186

3,200

= 0.0581 = 5.81 cM Incorrect MC

374f_8c53

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is affiliated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene C is associated with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.

Set #

Tetrad Genotypes

Progeny
Count

2,475

1,664

TOTAL =

4,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and C

distance =

½(61) + 3×(0)

4,200

30.5 + 0

4,200

30.5

4,200

= 0.0073 = 0.73 cM Incorrect distance =

½(2,475) + 3×(0)

4,200

1237.5 + 0

4,200

1237.5

4,200

= 0.2946 = 29.46 cM Incorrect distance =

½(0) + 3×(61)

4,200

0 + 183

4,200

183

4,200

= 0.0436 = 4.36 cM Incorrect distance =

½(61) + 3×(61)

4,200

30.5 + 183

4,200

213.5

4,200

= 0.0508 = 5.08 cM Incorrect distance =

½(1,664) + 3×(61)

4,200

832 + 183

4,200

1,015

4,200

= 0.2417 = 24.17 cM Correct distance =

½(1,664) + 3×(0)

4,200

832 + 0

4,200

832

4,200

= 0.1981 = 19.81 cM Incorrect MC

3e84_398a

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene W is associated with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.
Gene X is linked with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

3,758

2,360

TOTAL =

6,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes W and X

distance =

½(3,758) + 3×(0)

6,200

1,879 + 0

6,200

1,879

6,200

= 0.3031 = 30.31 cM Incorrect distance =

½(82) + 3×(82)

6,200

41 + 246

6,200

287

6,200

= 0.0463 = 4.63 cM Incorrect distance =

½(82) + 3×(0)

6,200

41 + 0

6,200

= 0.0066 = 0.66 cM Incorrect distance =

½(3,758) + 3×(82)

6,200

1,879 + 246

6,200

2,125

6,200

= 0.3427 = 34.27 cM Incorrect distance =

½(2,360 + 3,758) + 3×(82)

6,200

3,059 + 246

6,200

3,305

6,200

= 0.5331 = 53.31 cM Incorrect distance =

½(2,360) + 3×(82)

6,200

1,180 + 246

6,200

1,426

6,200

= 0.2300 = 23 cM Correct MC

eaa4_30de

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is connected with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene H is analogous to the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

1,110

1,038

TOTAL =

2,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and H

distance =

½(1,110) + 3×(0)

2,200

555 + 0

2,200

555

2,200

= 0.2523 = 25.23 cM Incorrect distance =

½(0) + 3×(52)

2,200

0 + 156

2,200

156

2,200

= 0.0709 = 7.09 cM Incorrect distance =

½(52) + 3×(0)

2,200

26 + 0

2,200

= 0.0118 = 1.18 cM Incorrect distance =

½(1,110) + 3×(52)

2,200

555 + 156

2,200

711

2,200

= 0.3232 = 32.32 cM Incorrect distance =

½(1,038) + 3×(52)

2,200

519 + 156

2,200

675

2,200

= 0.3068 = 30.68 cM Correct distance =

½(1,038) + 3×(0)

2,200

519 + 0

2,200

519

2,200

= 0.2359 = 23.59 cM Incorrect MC

c9fa_4d47

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene T is associated with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.
Gene W is linked with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

496

889

TOTAL =

1,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes T and W

distance =

½(15) + 3×(0)

1,400

7.5 + 0

1,400

7.5

1,400

= 0.0054 = 0.54 cM Incorrect distance =

½(889) + 3×(15)

1,400

444.5 + 45

1,400

489.5

1,400

= 0.3496 = 34.96 cM Incorrect distance =

½(496) + 3×(15)

1,400

248 + 45

1,400

293

1,400

= 0.2093 = 20.93 cM Correct distance =

½(15) + 3×(15)

1,400

7.5 + 45

1,400

52.5

1,400

= 0.0375 = 3.75 cM Incorrect distance =

½(889) + 3×(0)

1,400

444.5 + 0

1,400

444.5

1,400

= 0.3175 = 31.75 cM Incorrect distance =

½(496) + 3×(0)

1,400

248 + 0

1,400

248

1,400

= 0.1771 = 17.71 cM Incorrect MC

d6ed_aafc

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene W is correlated with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.
Gene X is linked with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

2,344

2,334

122

TOTAL =

4,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes W and X

distance =

½(2,334) + 3×(122)

4,800

1,167 + 366

4,800

1,533

4,800

= 0.3194 = 31.94 cM Correct distance =

½(122) + 3×(122)

4,800

61 + 366

4,800

427

4,800

= 0.0890 = 8.90 cM Incorrect distance =

½(2,344) + 3×(122)

4,800

1,172 + 366

4,800

1,538

4,800

= 0.3204 = 32.04 cM Incorrect distance =

½(2,344) + 3×(0)

4,800

1,172 + 0

4,800

1,172

4,800

= 0.2442 = 24.42 cM Incorrect distance =

½(0) + 3×(122)

4,800

0 + 366

4,800

366

4,800

= 0.0762 = 7.62 cM Incorrect distance =

½(2,334) + 3×(0)

4,800

1,167 + 0

4,800

1,167

4,800

= 0.2431 = 24.31 cM Incorrect MC

a08c_3378

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene X is connected with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.
Gene Y is correlated with the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

3,534

3,484

182

TOTAL =

7,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes X and Y

distance =

½(3,484 + 3,534) + 3×(182)

7,200

3,509 + 546

7,200

4,055

7,200

= 0.5632 = 56.32 cM Incorrect distance =

½(3,484) + 3×(182)

7,200

1,742 + 546

7,200

2,288

7,200

= 0.3178 = 31.78 cM Correct distance =

½(3,534) + 3×(0)

7,200

1,767 + 0

7,200

1,767

7,200

= 0.2454 = 24.54 cM Incorrect distance =

½(0) + 3×(182)

7,200

0 + 546

7,200

546

7,200

= 0.0758 = 7.58 cM Incorrect distance =

½(3,534) + 3×(182)

7,200

1,767 + 546

7,200

2,313

7,200

= 0.3212 = 32.12 cM Incorrect distance =

½(3,484) + 3×(0)

7,200

1,742 + 0

7,200

1,742

7,200

= 0.2419 = 24.19 cM Incorrect MC

3a19_93a9

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is affiliated with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene N is associated with the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

1,176

1,370

TOTAL =

2,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and N

distance =

½(0) + 3×(54)

2,600

0 + 162

2,600

162

2,600

= 0.0623 = 6.23 cM Incorrect distance =

½(1,370) + 3×(0)

2,600

685 + 0

2,600

685

2,600

= 0.2635 = 26.35 cM Incorrect distance =

½(1,176) + 3×(54)

2,600

588 + 162

2,600

750

2,600

= 0.2885 = 28.85 cM Correct distance =

½(54) + 3×(0)

2,600

27 + 0

2,600

= 0.0104 = 1.04 cM Incorrect distance =

½(1,176) + 3×(0)

2,600

588 + 0

2,600

588

2,600

= 0.2262 = 22.62 cM Incorrect distance =

½(54) + 3×(54)

2,600

27 + 162

2,600

189

2,600

= 0.0727 = 7.27 cM Incorrect MC

b27c_4e39

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is related to the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene D is connected with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.

Set #

Tetrad Genotypes

Progeny
Count

4,035

3,040

125

TOTAL =

7,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and D

distance =

½(4,035) + 3×(125)

7,200

2017.5 + 375

7,200

2392.5

7,200

= 0.3323 = 33.23 cM Incorrect distance =

½(125) + 3×(0)

7,200

62.5 + 0

7,200

62.5

7,200

= 0.0087 = 0.87 cM Incorrect distance =

½(125) + 3×(125)

7,200

62.5 + 375

7,200

437.5

7,200

= 0.0608 = 6.08 cM Incorrect distance =

½(3,040 + 4,035) + 3×(125)

7,200

3537.5 + 375

7,200

3912.5

7,200

= 0.5434 = 54.34 cM Incorrect distance =

½(3,040) + 3×(125)

7,200

1,520 + 375

7,200

1,895

7,200

= 0.2632 = 26.32 cM Correct distance =

½(4,035) + 3×(0)

7,200

2017.5 + 0

7,200

2017.5

7,200

= 0.2802 = 28.02 cM Incorrect MC

ecfe_c650

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is affiliated with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene R is connected with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

1,202

1,547

TOTAL =

2,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and R

distance =

½(1,202) + 3×(51)

2,800

601 + 153

2,800

754

2,800

= 0.2693 = 26.93 cM Correct distance =

½(1,202) + 3×(0)

2,800

601 + 0

2,800

601

2,800

= 0.2146 = 21.46 cM Incorrect distance =

½(1,202 + 1,547) + 3×(51)

2,800

1374.5 + 153

2,800

1527.5

2,800

= 0.5455 = 54.55 cM Incorrect distance =

½(1,547) + 3×(0)

2,800

773.5 + 0

2,800

773.5

2,800

= 0.2762 = 27.62 cM Incorrect distance =

½(51) + 3×(51)

2,800

25.5 + 153

2,800

178.5

2,800

= 0.0638 = 6.38 cM Incorrect distance =

½(1,547) + 3×(51)

2,800

773.5 + 153

2,800

926.5

2,800

= 0.3309 = 33.09 cM Incorrect MC

4fa2_c0c8

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is affiliated with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene W is correlated with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

2,680

5,040

TOTAL =

7,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and W

distance =

½(80) + 3×(0)

7,800

40 + 0

7,800

= 0.0051 = 0.51 cM Incorrect distance =

½(0) + 3×(80)

7,800

0 + 240

7,800

240

7,800

= 0.0308 = 3.08 cM Incorrect distance =

½(5,040) + 3×(0)

7,800

2,520 + 0

7,800

2,520

7,800

= 0.3231 = 32.31 cM Incorrect distance =

½(80) + 3×(80)

7,800

40 + 240

7,800

280

7,800

= 0.0359 = 3.59 cM Incorrect distance =

½(2,680) + 3×(0)

7,800

1,340 + 0

7,800

1,340

7,800

= 0.1718 = 17.18 cM Incorrect distance =

½(2,680) + 3×(80)

7,800

1,340 + 240

7,800

1,580

7,800

= 0.2026 = 20.26 cM Correct MC

d572_b6c4

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is connected with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene Y is analogous to the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

2,527

1,616

TOTAL =

4,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and Y

distance =

½(0) + 3×(57)

4,200

0 + 171

4,200

171

4,200

= 0.0407 = 4.07 cM Incorrect distance =

½(2,527) + 3×(57)

4,200

1263.5 + 171

4,200

1434.5

4,200

= 0.3415 = 34.15 cM Incorrect distance =

½(57) + 3×(57)

4,200

28.5 + 171

4,200

199.5

4,200

= 0.0475 = 4.75 cM Incorrect distance =

½(57) + 3×(0)

4,200

28.5 + 0

4,200

28.5

4,200

= 0.0068 = 0.68 cM Incorrect distance =

½(1,616) + 3×(57)

4,200

808 + 171

4,200

979

4,200

= 0.2331 = 23.31 cM Correct distance =

½(1,616 + 2,527) + 3×(57)

4,200

2071.5 + 171

4,200

2242.5

4,200

= 0.5339 = 53.39 cM Incorrect MC

3cd5_50eb

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is associated with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene P is related to the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.

Set #

Tetrad Genotypes

Progeny
Count

137

3,522

4,941

TOTAL =

8,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and P

distance =

½(4,941) + 3×(137)

8,600

2470.5 + 411

8,600

2881.5

8,600

= 0.3351 = 33.51 cM Incorrect distance =

½(4,941) + 3×(0)

8,600

2470.5 + 0

8,600

2470.5

8,600

= 0.2873 = 28.73 cM Incorrect distance =

½(0) + 3×(137)

8,600

0 + 411

8,600

411

8,600

= 0.0478 = 4.78 cM Incorrect distance =

½(137) + 3×(137)

8,600

68.5 + 411

8,600

479.5

8,600

= 0.0558 = 5.58 cM Incorrect distance =

½(3,522) + 3×(137)

8,600

1,761 + 411

8,600

2,172

8,600

= 0.2526 = 25.26 cM Correct distance =

½(3,522 + 4,941) + 3×(137)

8,600

4231.5 + 411

8,600

4642.5

8,600

= 0.5398 = 53.98 cM Incorrect MC

ca7e_a214

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene E is correlated with the 'elephant' phenotype. A budding yeast that is homozygous recessive for Gene E cells absorb excessive amounts of liquid, resulting in giant, swollen cells.
Gene H is correlated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

3,832

2,292

TOTAL =

6,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes E and H

distance =

½(2,292 + 3,832) + 3×(76)

6,200

3,062 + 228

6,200

3,290

6,200

= 0.5306 = 53.06 cM Incorrect distance =

½(0) + 3×(76)

6,200

0 + 228

6,200

228

6,200

= 0.0368 = 3.68 cM Incorrect distance =

½(2,292) + 3×(76)

6,200

1,146 + 228

6,200

1,374

6,200

= 0.2216 = 22.16 cM Correct distance =

½(3,832) + 3×(76)

6,200

1,916 + 228

6,200

2,144

6,200

= 0.3458 = 34.58 cM Incorrect distance =

½(76) + 3×(0)

6,200

38 + 0

6,200

= 0.0061 = 0.61 cM Incorrect distance =

½(2,292) + 3×(0)

6,200

1,146 + 0

6,200

1,146

6,200

= 0.1848 = 18.48 cM Incorrect MC

f93e_a528

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is analogous to the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene C is linked with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.

Set #

Tetrad Genotypes

Progeny
Count

1,282

1,070

TOTAL =

2,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and C

distance =

½(1,282) + 3×(0)

2,400

641 + 0

2,400

641

2,400

= 0.2671 = 26.71 cM Incorrect distance =

½(48) + 3×(48)

2,400

24 + 144

2,400

168

2,400

= 0.0700 = 7 cM Incorrect distance =

½(48) + 3×(0)

2,400

24 + 0

2,400

= 0.0100 = 1 cM Incorrect distance =

½(1,282) + 3×(48)

2,400

641 + 144

2,400

785

2,400

= 0.3271 = 32.71 cM Incorrect distance =

½(1,070 + 1,282) + 3×(48)

2,400

1,176 + 144

2,400

1,320

2,400

= 0.5500 = 55 cM Incorrect distance =

½(1,070) + 3×(48)

2,400

535 + 144

2,400

679

2,400

= 0.2829 = 28.29 cM Correct MC

3314_0410

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene R is analogous to the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.
Gene X is linked with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

2,686

4,831

TOTAL =

7,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes R and X

distance =

½(2,686 + 4,831) + 3×(83)

7,600

3758.5 + 249

7,600

4007.5

7,600

= 0.5273 = 52.73 cM Incorrect distance =

½(4,831) + 3×(0)

7,600

2415.5 + 0

7,600

2415.5

7,600

= 0.3178 = 31.78 cM Incorrect distance =

½(83) + 3×(83)

7,600

41.5 + 249

7,600

290.5

7,600

= 0.0382 = 3.82 cM Incorrect distance =

½(2,686) + 3×(83)

7,600

1,343 + 249

7,600

1,592

7,600

= 0.2095 = 20.95 cM Correct distance =

½(83) + 3×(0)

7,600

41.5 + 0

7,600

41.5

7,600

= 0.0055 = 0.55 cM Incorrect distance =

½(0) + 3×(83)

7,600

0 + 249

7,600

249

7,600

= 0.0328 = 3.28 cM Incorrect MC

3833_2889

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene H is affiliated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.
Gene T is associated with the 'toxic' phenotype. A budding yeast that is homozygous recessive for Gene T secretes a toxic compound that inhibits or kills other microbial colonies nearby.

Set #

Tetrad Genotypes

Progeny
Count

1,060

1,293

TOTAL =

2,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes H and T

distance =

½(47) + 3×(47)

2,400

23.5 + 141

2,400

164.5

2,400

= 0.0685 = 6.85 cM Incorrect distance =

½(1,293) + 3×(0)

2,400

646.5 + 0

2,400

646.5

2,400

= 0.2694 = 26.94 cM Incorrect distance =

½(1,060) + 3×(0)

2,400

530 + 0

2,400

530

2,400

= 0.2208 = 22.08 cM Incorrect distance =

½(1,060) + 3×(47)

2,400

530 + 141

2,400

671

2,400

= 0.2796 = 27.96 cM Correct distance =

½(1,293) + 3×(47)

2,400

646.5 + 141

2,400

787.5

2,400

= 0.3281 = 32.81 cM Incorrect distance =

½(1,060 + 1,293) + 3×(47)

2,400

1176.5 + 141

2,400

1317.5

2,400

= 0.5490 = 54.90 cM Incorrect MC

795e_293b

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is linked with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene X is analogous to the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

3,621

2,672

107

TOTAL =

6,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and X

distance =

½(2,672) + 3×(107)

6,400

1,336 + 321

6,400

1,657

6,400

= 0.2589 = 25.89 cM Correct distance =

½(2,672 + 3,621) + 3×(107)

6,400

3146.5 + 321

6,400

3467.5

6,400

= 0.5418 = 54.18 cM Incorrect distance =

½(2,672) + 3×(0)

6,400

1,336 + 0

6,400

1,336

6,400

= 0.2087 = 20.88 cM Incorrect distance =

½(0) + 3×(107)

6,400

0 + 321

6,400

321

6,400

= 0.0502 = 5.02 cM Incorrect distance =

½(3,621) + 3×(107)

6,400

1810.5 + 321

6,400

2131.5

6,400

= 0.3330 = 33.30 cM Incorrect distance =

½(107) + 3×(0)

6,400

53.5 + 0

6,400

53.5

6,400

= 0.0084 = 0.84 cM Incorrect MC

c416_6a71

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is analogous to the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene R is affiliated with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

940

636

TOTAL =

1,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and R

distance =

½(24) + 3×(24)

1,600

12 + 72

1,600

= 0.0525 = 5.25 cM Incorrect distance =

½(940) + 3×(0)

1,600

470 + 0

1,600

470

1,600

= 0.2938 = 29.38 cM Incorrect distance =

½(636) + 3×(24)

1,600

318 + 72

1,600

390

1,600

= 0.2437 = 24.38 cM Correct distance =

½(636 + 940) + 3×(24)

1,600

788 + 72

1,600

860

1,600

= 0.5375 = 53.75 cM Incorrect distance =

½(940) + 3×(24)

1,600

470 + 72

1,600

542

1,600

= 0.3387 = 33.88 cM Incorrect distance =

½(24) + 3×(0)

1,600

12 + 0

1,600

= 0.0075 = 0.75 cM Incorrect MC

a56b_7800

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene N is related to the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.
Gene R is linked with the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

1,698

1,252

TOTAL =

3,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes N and R

distance =

½(1,252 + 1,698) + 3×(50)

3,000

1,475 + 150

3,000

1,625

3,000

= 0.5417 = 54.17 cM Incorrect distance =

½(1,252) + 3×(0)

3,000

626 + 0

3,000

626

3,000

= 0.2087 = 20.87 cM Incorrect distance =

½(1,698) + 3×(50)

3,000

849 + 150

3,000

999

3,000

= 0.3330 = 33.30 cM Incorrect distance =

½(50) + 3×(50)

3,000

25 + 150

3,000

175

3,000

= 0.0583 = 5.83 cM Incorrect distance =

½(1,252) + 3×(50)

3,000

626 + 150

3,000

776

3,000

= 0.2587 = 25.87 cM Correct distance =

½(0) + 3×(50)

3,000

0 + 150

3,000

150

3,000

= 0.0500 = 5 cM Incorrect MC

dfec_d716

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene B is linked with the 'bubbly' phenotype. A budding yeast that is homozygous recessive for Gene B produces excessive gas bubbles during growth, causing foamy appearance of the media.
Gene N is linked with the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

2,846

5,268

TOTAL =

8,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes B and N

distance =

½(0) + 3×(86)

8,200

0 + 258

8,200

258

8,200

= 0.0315 = 3.15 cM Incorrect distance =

½(2,846) + 3×(86)

8,200

1,423 + 258

8,200

1,681

8,200

= 0.2050 = 20.50 cM Correct distance =

½(5,268) + 3×(86)

8,200

2,634 + 258

8,200

2,892

8,200

= 0.3527 = 35.27 cM Incorrect distance =

½(2,846) + 3×(0)

8,200

1,423 + 0

8,200

1,423

8,200

= 0.1735 = 17.35 cM Incorrect distance =

½(86) + 3×(86)

8,200

43 + 258

8,200

301

8,200

= 0.0367 = 3.67 cM Incorrect distance =

½(5,268) + 3×(0)

8,200

2,634 + 0

8,200

2,634

8,200

= 0.3212 = 32.12 cM Incorrect MC

dc29_d62c

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is affiliated with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene W is associated with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

3,178

5,723

TOTAL =

9,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and W

distance =

½(99) + 3×(0)

9,000

49.5 + 0

9,000

49.5

9,000

= 0.0055 = 0.55 cM Incorrect distance =

½(5,723) + 3×(0)

9,000

2861.5 + 0

9,000

2861.5

9,000

= 0.3179 = 31.79 cM Incorrect distance =

½(3,178 + 5,723) + 3×(99)

9,000

4450.5 + 297

9,000

4747.5

9,000

= 0.5275 = 52.75 cM Incorrect distance =

½(0) + 3×(99)

9,000

0 + 297

9,000

297

9,000

= 0.0330 = 3.30 cM Incorrect distance =

½(3,178) + 3×(0)

9,000

1,589 + 0

9,000

1,589

9,000

= 0.1766 = 17.66 cM Incorrect distance =

½(3,178) + 3×(99)

9,000

1,589 + 297

9,000

1,886

9,000

= 0.2096 = 20.96 cM Correct MC

2b37_144e

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is related to the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene R is related to the 'rusty' phenotype. A budding yeast that is homozygous recessive for Gene R colonies develop a reddish-brown pigmentation, reminiscent of rusted metal.

Set #

Tetrad Genotypes

Progeny
Count

2,092

1,824

TOTAL =

4,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and R

distance =

½(1,824) + 3×(84)

4,000

912 + 252

4,000

1,164

4,000

= 0.2910 = 29.10 cM Correct distance =

½(1,824) + 3×(0)

4,000

912 + 0

4,000

912

4,000

= 0.2280 = 22.80 cM Incorrect distance =

½(2,092) + 3×(0)

4,000

1,046 + 0

4,000

1,046

4,000

= 0.2615 = 26.15 cM Incorrect distance =

½(2,092) + 3×(84)

4,000

1,046 + 252

4,000

1,298

4,000

= 0.3245 = 32.45 cM Incorrect distance =

½(84) + 3×(0)

4,000

42 + 0

4,000

= 0.0105 = 1.05 cM Incorrect distance =

½(0) + 3×(84)

4,000

0 + 252

4,000

252

4,000

= 0.0630 = 6.30 cM Incorrect MC

78a5_fe3a

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene P is linked with the 'pebble' phenotype. A budding yeast that is homozygous recessive for Gene P produces colonies with a rough, uneven surface that resembles a collection of tiny pebbles.
Gene Y is analogous to the 'yolk' phenotype. A budding yeast that is homozygous recessive for Gene Y cells develop a dense, yellowish core that resembles an egg yolk when viewed under a microscope.

Set #

Tetrad Genotypes

Progeny
Count

139

3,278

4,183

TOTAL =

7,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes P and Y

distance =

½(3,278) + 3×(139)

7,600

1,639 + 417

7,600

2,056

7,600

= 0.2705 = 27.05 cM Correct distance =

½(3,278 + 4,183) + 3×(139)

7,600

3730.5 + 417

7,600

4147.5

7,600

= 0.5457 = 54.57 cM Incorrect distance =

½(0) + 3×(139)

7,600

0 + 417

7,600

417

7,600

= 0.0549 = 5.49 cM Incorrect distance =

½(139) + 3×(139)

7,600

69.5 + 417

7,600

486.5

7,600

= 0.0640 = 6.40 cM Incorrect distance =

½(139) + 3×(0)

7,600

69.5 + 0

7,600

69.5

7,600

= 0.0091 = 0.91 cM Incorrect distance =

½(3,278) + 3×(0)

7,600

1,639 + 0

7,600

1,639

7,600

= 0.2157 = 21.57 cM Incorrect MC

7ff8_b6c4

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is related to the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene W is linked with the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

3,216

2,480

104

TOTAL =

5,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and W

distance =

½(104) + 3×(104)

5,800

52 + 312

5,800

364

5,800

= 0.0628 = 6.28 cM Incorrect distance =

½(2,480) + 3×(0)

5,800

1,240 + 0

5,800

1,240

5,800

= 0.2138 = 21.38 cM Incorrect distance =

½(3,216) + 3×(104)

5,800

1,608 + 312

5,800

1,920

5,800

= 0.3310 = 33.10 cM Incorrect distance =

½(2,480 + 3,216) + 3×(104)

5,800

2,848 + 312

5,800

3,160

5,800

= 0.5448 = 54.48 cM Incorrect distance =

½(3,216) + 3×(0)

5,800

1,608 + 0

5,800

1,608

5,800

= 0.2772 = 27.72 cM Incorrect distance =

½(2,480) + 3×(104)

5,800

1,240 + 312

5,800

1,552

5,800

= 0.2676 = 26.76 cM Correct MC

1141_1e45

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is linked with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene M is analogous to the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

2,096

3,433

TOTAL =

5,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and M

distance =

½(71) + 3×(0)

5,600

35.5 + 0

5,600

35.5

5,600

= 0.0063 = 0.63 cM Incorrect distance =

½(0) + 3×(71)

5,600

0 + 213

5,600

213

5,600

= 0.0380 = 3.80 cM Incorrect distance =

½(3,433) + 3×(0)

5,600

1716.5 + 0

5,600

1716.5

5,600

= 0.3065 = 30.65 cM Incorrect distance =

½(71) + 3×(71)

5,600

35.5 + 213

5,600

248.5

5,600

= 0.0444 = 4.44 cM Incorrect distance =

½(2,096) + 3×(71)

5,600

1,048 + 213

5,600

1,261

5,600

= 0.2252 = 22.52 cM Correct distance =

½(3,433) + 3×(71)

5,600

1716.5 + 213

5,600

1929.5

5,600

= 0.3446 = 34.46 cM Incorrect MC

594b_e459

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene A is connected with the 'amber' phenotype. A budding yeast that is homozygous recessive for Gene A cells develop a rich yellow-orange pigmentation, giving the colony a warm, amber hue.
Gene X is associated with the 'xenon' phenotype. A budding yeast that is homozygous recessive for Gene X cells emit a faint glow under UV light, as if they were fluorescent.

Set #

Tetrad Genotypes

Progeny
Count

2,215

1,340

TOTAL =

3,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes A and X

distance =

½(1,340) + 3×(45)

3,600

670 + 135

3,600

805

3,600

= 0.2236 = 22.36 cM Correct distance =

½(45) + 3×(45)

3,600

22.5 + 135

3,600

157.5

3,600

= 0.0437 = 4.38 cM Incorrect distance =

½(1,340 + 2,215) + 3×(45)

3,600

1777.5 + 135

3,600

1912.5

3,600

= 0.5312 = 53.12 cM Incorrect distance =

½(45) + 3×(0)

3,600

22.5 + 0

3,600

22.5

3,600

= 0.0063 = 0.62 cM Incorrect distance =

½(1,340) + 3×(0)

3,600

670 + 0

3,600

670

3,600

= 0.1861 = 18.61 cM Incorrect distance =

½(2,215) + 3×(0)

3,600

1107.5 + 0

3,600

1107.5

3,600

= 0.3076 = 30.76 cM Incorrect MC

573a_db09

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene H is connected with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.
Gene K is related to the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.

Set #

Tetrad Genotypes

Progeny
Count

102

2,062

2,236

TOTAL =

4,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes H and K

distance =

½(0) + 3×(102)

4,400

0 + 306

4,400

306

4,400

= 0.0695 = 6.95 cM Incorrect distance =

½(2,062) + 3×(102)

4,400

1,031 + 306

4,400

1,337

4,400

= 0.3039 = 30.39 cM Correct distance =

½(102) + 3×(0)

4,400

51 + 0

4,400

= 0.0116 = 1.16 cM Incorrect distance =

½(102) + 3×(102)

4,400

51 + 306

4,400

357

4,400

= 0.0811 = 8.11 cM Incorrect distance =

½(2,062) + 3×(0)

4,400

1,031 + 0

4,400

1,031

4,400

= 0.2343 = 23.43 cM Incorrect distance =

½(2,236) + 3×(0)

4,400

1,118 + 0

4,400

1,118

4,400

= 0.2541 = 25.41 cM Incorrect MC

74fc_6034

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene F is linked with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.
Gene H is correlated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

1,674

2,053

TOTAL =

3,800

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes F and H

distance =

½(1,674 + 2,053) + 3×(73)

3,800

1863.5 + 219

3,800

2082.5

3,800

= 0.5480 = 54.80 cM Incorrect distance =

½(1,674) + 3×(73)

3,800

837 + 219

3,800

1,056

3,800

= 0.2779 = 27.79 cM Correct distance =

½(0) + 3×(73)

3,800

0 + 219

3,800

219

3,800

= 0.0576 = 5.76 cM Incorrect distance =

½(73) + 3×(0)

3,800

36.5 + 0

3,800

36.5

3,800

= 0.0096 = 0.96 cM Incorrect distance =

½(2,053) + 3×(0)

3,800

1026.5 + 0

3,800

1026.5

3,800

= 0.2701 = 27.01 cM Incorrect distance =

½(73) + 3×(73)

3,800

36.5 + 219

3,800

255.5

3,800

= 0.0672 = 6.72 cM Incorrect MC

ada8_6a51

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene M is related to the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.
Gene N is connected with the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

512

872

TOTAL =

1,400

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes M and N

distance =

½(512) + 3×(16)

1,400

256 + 48

1,400

304

1,400

= 0.2171 = 21.71 cM Correct distance =

½(16) + 3×(0)

1,400

8 + 0

1,400

= 0.0057 = 0.57 cM Incorrect distance =

½(512) + 3×(0)

1,400

256 + 0

1,400

256

1,400

= 0.1829 = 18.29 cM Incorrect distance =

½(16) + 3×(16)

1,400

8 + 48

1,400

= 0.0400 = 4 cM Incorrect distance =

½(872) + 3×(16)

1,400

436 + 48

1,400

484

1,400

= 0.3457 = 34.57 cM Incorrect distance =

½(512 + 872) + 3×(16)

1,400

692 + 48

1,400

740

1,400

= 0.5286 = 52.86 cM Incorrect MC

c086_06e8

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is correlated with the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene W is analogous to the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

2,740

4,161

TOTAL =

7,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and W

distance =

½(2,740 + 4,161) + 3×(99)

7,000

3450.5 + 297

7,000

3747.5

7,000

= 0.5354 = 53.54 cM Incorrect distance =

½(2,740) + 3×(99)

7,000

1,370 + 297

7,000

1,667

7,000

= 0.2381 = 23.81 cM Correct distance =

½(4,161) + 3×(0)

7,000

2080.5 + 0

7,000

2080.5

7,000

= 0.2972 = 29.72 cM Incorrect distance =

½(99) + 3×(0)

7,000

49.5 + 0

7,000

49.5

7,000

= 0.0071 = 0.71 cM Incorrect distance =

½(2,740) + 3×(0)

7,000

1,370 + 0

7,000

1,370

7,000

= 0.1957 = 19.57 cM Incorrect distance =

½(4,161) + 3×(99)

7,000

2080.5 + 297

7,000

2377.5

7,000

= 0.3396 = 33.96 cM Incorrect MC

7e36_a721

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene N is analogous to the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.
Gene W is related to the 'webbed' phenotype. A budding yeast that is homozygous recessive for Gene W colonies produce delicate, web-like strands that connect neighboring colonies in a cobweb pattern.

Set #

Tetrad Genotypes

Progeny
Count

2,626

1,524

TOTAL =

4,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes N and W

distance =

½(50) + 3×(50)

4,200

25 + 150

4,200

175

4,200

= 0.0417 = 4.17 cM Incorrect distance =

½(1,524) + 3×(50)

4,200

762 + 150

4,200

912

4,200

= 0.2171 = 21.71 cM Correct distance =

½(50) + 3×(0)

4,200

25 + 0

4,200

= 0.0060 = 0.60 cM Incorrect distance =

½(2,626) + 3×(0)

4,200

1,313 + 0

4,200

1,313

4,200

= 0.3126 = 31.26 cM Incorrect distance =

½(1,524) + 3×(0)

4,200

762 + 0

4,200

762

4,200

= 0.1814 = 18.14 cM Incorrect distance =

½(2,626) + 3×(50)

4,200

1,313 + 150

4,200

1,463

4,200

= 0.3483 = 34.83 cM Incorrect MC

889f_8a6a

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene D is related to the 'doubled' phenotype. A budding yeast that is homozygous recessive for Gene D cells display double or multiple budding, with several buds emerging simultaneously.
Gene H is connected with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

1,972

1,928

100

TOTAL =

4,000

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes D and H

distance =

½(1,972) + 3×(100)

4,000

986 + 300

4,000

1,286

4,000

= 0.3215 = 32.15 cM Incorrect distance =

½(1,928) + 3×(100)

4,000

964 + 300

4,000

1,264

4,000

= 0.3160 = 31.60 cM Correct distance =

½(1,928 + 1,972) + 3×(100)

4,000

1,950 + 300

4,000

2,250

4,000

= 0.5625 = 56.25 cM Incorrect distance =

½(0) + 3×(100)

4,000

0 + 300

4,000

300

4,000

= 0.0750 = 7.50 cM Incorrect distance =

½(100) + 3×(0)

4,000

50 + 0

4,000

= 0.0125 = 1.25 cM Incorrect distance =

½(1,928) + 3×(0)

4,000

964 + 0

4,000

964

4,000

= 0.2410 = 24.10 cM Incorrect MC

0432_3bb2

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene K is linked with the 'knotted' phenotype. A budding yeast that is homozygous recessive for Gene K cells grow in twisted, coiled shapes, resulting in a knotted or gnarled appearance.
Gene N is related to the 'nude' phenotype. A budding yeast that is homozygous recessive for Gene N cells have an unusually smooth surface with no visible external features or textures.

Set #

Tetrad Genotypes

Progeny
Count

1,329

1,212

TOTAL =

2,600

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes K and N

distance =

½(1,212 + 1,329) + 3×(59)

2,600

1270.5 + 177

2,600

1447.5

2,600

= 0.5567 = 55.67 cM Incorrect distance =

½(1,329) + 3×(0)

2,600

664.5 + 0

2,600

664.5

2,600

= 0.2556 = 25.56 cM Incorrect distance =

½(1,212) + 3×(59)

2,600

606 + 177

2,600

783

2,600

= 0.3012 = 30.12 cM Correct distance =

½(1,329) + 3×(59)

2,600

664.5 + 177

2,600

841.5

2,600

= 0.3237 = 32.37 cM Incorrect distance =

½(59) + 3×(0)

2,600

29.5 + 0

2,600

29.5

2,600

= 0.0113 = 1.13 cM Incorrect distance =

½(1,212) + 3×(0)

2,600

606 + 0

2,600

606

2,600

= 0.2331 = 23.31 cM Incorrect MC

61f8_e4e3

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene H is analogous to the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.
Gene M is correlated with the 'militant' phenotype. A budding yeast that is homozygous recessive for Gene M colonies are small, dense, and secrete compounds that inhibit the growth of nearby colonies.

Set #

Tetrad Genotypes

Progeny
Count

1,310

1,840

TOTAL =

3,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes H and M

distance =

½(50) + 3×(50)

3,200

25 + 150

3,200

175

3,200

= 0.0547 = 5.47 cM Incorrect distance =

½(1,310 + 1,840) + 3×(50)

3,200

1,575 + 150

3,200

1,725

3,200

= 0.5391 = 53.91 cM Incorrect distance =

½(1,840) + 3×(50)

3,200

920 + 150

3,200

1,070

3,200

= 0.3344 = 33.44 cM Incorrect distance =

½(1,310) + 3×(50)

3,200

655 + 150

3,200

805

3,200

= 0.2516 = 25.16 cM Correct distance =

½(50) + 3×(0)

3,200

25 + 0

3,200

= 0.0078 = 0.78 cM Incorrect distance =

½(1,310) + 3×(0)

3,200

655 + 0

3,200

655

3,200

= 0.2047 = 20.47 cM Incorrect MC

9e5d_03a3

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is associated with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene F is connected with the 'fuzzy' phenotype. A budding yeast that is homozygous recessive for Gene F colonies are covered in soft, fine filaments, giving them a fuzzy, cotton-like texture.

Set #

Tetrad Genotypes

Progeny
Count

1,948

3,186

TOTAL =

5,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and F

distance =

½(1,948 + 3,186) + 3×(66)

5,200

2,567 + 198

5,200

2,765

5,200

= 0.5317 = 53.17 cM Incorrect distance =

½(0) + 3×(66)

5,200

0 + 198

5,200

198

5,200

= 0.0381 = 3.81 cM Incorrect distance =

½(3,186) + 3×(66)

5,200

1,593 + 198

5,200

1,791

5,200

= 0.3444 = 34.44 cM Incorrect distance =

½(66) + 3×(66)

5,200

33 + 198

5,200

231

5,200

= 0.0444 = 4.44 cM Incorrect distance =

½(1,948) + 3×(0)

5,200

974 + 0

5,200

974

5,200

= 0.1873 = 18.73 cM Incorrect distance =

½(1,948) + 3×(66)

5,200

974 + 198

5,200

1,172

5,200

= 0.2254 = 22.54 cM Correct MC

0130_e5e6

Unordered Tetrad Two Gene Mapping

Characteristics of Recessive Phenotypes

Gene C is correlated with the 'clumpy' phenotype. A budding yeast that is homozygous recessive for Gene C grows in dense, irregular clusters, with cells clumping together rather than spreading smoothly.
Gene H is affiliated with the 'hairy' phenotype. A budding yeast that is homozygous recessive for Gene H cells develop long, thread-like filaments that extend outward, creating a hairy, shaggy texture on the colony.

Set #

Tetrad Genotypes

Progeny
Count

1,032

1,117

TOTAL =

2,200

The resulting phenotypes are summarized in the table above.

Step-by-Step Instructions

Step 1: Find the row for the Parental Type for all three genes.
Step 2: Looking at only your two genes, assign PD, NPD, TT.
Step 3: Determine if the two genes are linked.

PD >> NPD → linked; PD ≈ NPD → unlinked

Step 4: Determine the map distance between the two genes.

D = ½ (TT + 6 NPD) / total = (3 NPD + ½ TT) / total

Determine the distance between the two genes C and H

distance =

½(1,117) + 3×(0)

2,200

558.5 + 0

2,200

558.5

2,200

= 0.2539 = 25.39 cM Incorrect distance =

½(51) + 3×(51)

2,200

25.5 + 153

2,200

178.5

2,200

= 0.0811 = 8.11 cM Incorrect distance =

½(1,032 + 1,117) + 3×(51)

2,200

1074.5 + 153

2,200

1227.5

2,200

= 0.5580 = 55.80 cM Incorrect distance =

½(0) + 3×(51)

2,200

0 + 153

2,200

153

2,200

= 0.0695 = 6.95 cM Incorrect distance =

½(51) + 3×(0)

2,200

25.5 + 0

2,200

25.5

2,200

= 0.0116 = 1.16 cM Incorrect distance =

½(1,032) + 3×(51)

2,200

516 + 153

2,200

669

2,200

= 0.3041 = 30.41 cM Correct