3: DNA Profiling
Students use blood typing agglutination tests, HLA genotyping, gel electrophoresis band patterns, and DNA fingerprinting techniques to solve paternity disputes and forensic identification problems.
LibreTexts reference: Chapter 3: DNA Profiling and Techniques 
True/False Statements About English Palindromes
Click to show True/False Statements About English Palindromes example problem
Blood Typing Test Results
Click to show Blood Typing Test Results example problem
During a blood typing test, anti-A, anti-B, and anti-D antibodies are added to a blood sample along with a control. A visible reaction indicates the presence or absence of the corresponding antigens.
What would the test results look like for someone with B- blood type?
HLA Genotype Inheritance (2 Markers, Black)
Click to show HLA Genotype Inheritance (2 Markers, Black) example problem
HLA genotyping serves as a key component in the field of immunogenetics. It is used for understanding individual variations in immune responses. This molecular technique identifies unique alleles on paired chromosomes. It's particularly vital in organ transplantation for matching donors and recipients. Finding a correct match reduces the chance for graft rejection.
A mother has a HLA genotype of A3,B8 on one chromosome and A2,B4 on the other chromosome.
The father has a HLA genotype of A9,B3 on one chromosome and A4,B5 on the other chromosome.
Which one of the following combinations is a possible genotype for their offspring?
HLA Genotyping Problem
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HLA genotyping serves as a key component in the field of immunogenetics. It is used for understanding individual variations in immune responses. This molecular technique identifies unique alleles on paired chromosomes. It's particularly vital in organ transplantation for matching donors and recipients. Finding a correct match reduces the chance for graft rejection.
A mother has a HLA genotype of A7,B4 on one chromosome and A1,B9 on the other chromosome.
The father has a HLA genotype of A5,B7 on one chromosome and A8,B3 on the other chromosome.
Which one of the following combinations is a possible genotype for their offspring?
HLA Genotype Inheritance (3 Markers, Color)
Click to show HLA Genotype Inheritance (3 Markers, Color) example problem
HLA genotyping serves as a key component in the field of immunogenetics. It is used for understanding individual variations in immune responses. This molecular technique identifies unique alleles on paired chromosomes. It's particularly vital in organ transplantation for matching donors and recipients. Finding a correct match reduces the chance for graft rejection.
A mother has a HLA genotype of A1,B8,C1 on one chromosome and A7,B4,C8 on the other chromosome.
The father has a HLA genotype of A9,B7,C3 on one chromosome and A4,B1,C4 on the other chromosome.
Which one of the following combinations is a possible genotype for their offspring?
Restriction Enzyme DNA Strand Products (10 Length, 3 Sites)
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DNA Strand Question:
Examine the DNA strand shown below. The table highlights a specific portion of a much longer DNA molecule to focus on the region containing restriction sites.
| MfeI | KspI | MfeI | KspI | MfeI | |||||||||||||||||||
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | |||||||||||||
Two (2) distinct types of restriction enzyme recognition sites, MfeI and KspI, are labeled at the top of this DNA segment.
Note: The dashes at both ends of the strand indicate that the next restriction site is far away and outside the visible region. Because this segment is part of a much larger molecule, any uncut or very large fragments will not travel into the gel and will appear to be stuck in the well.
Determine the sizes of the DNA bands that would appear on an agarose gel after digestion with MfeI only.
Restriction Enzyme DNA Fragment Products (13 Length, 3 Sites)
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DNA Fragment Question:Shown below is a short DNA fragment that is only 13 kb in length. This fragment has been isolated for restriction enzyme analysis.
| AluI | PacI | AluI | PacI | AluI | |||||||||||||||||||||||||
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | ||||||||||||||||
Two (2) distinct types of restriction enzyme recognition sites, AluI and PacI, are labeled at the top of this DNA segment.
Determine the sizes of the DNA bands that would appear on an agarose gel after digestion with AluI only.
Restriction Enzyme DNA Strand Products (16 Length, 4 Sites)
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DNA Strand Question:
Examine the DNA strand shown below. The table highlights a specific portion of a much longer DNA molecule to focus on the region containing restriction sites.
| SciI | PsiI | SciI | PsiI | SciI | PsiI | SciI | |||||||||||||||||||||||||||||
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | |||||||||||||||||||
Two (2) distinct types of restriction enzyme recognition sites, SciI and PsiI, are labeled at the top of this DNA segment.
Note: The dashes at both ends of the strand indicate that the next restriction site is far away and outside the visible region. Because this segment is part of a much larger molecule, any uncut or very large fragments will not travel into the gel and will appear to be stuck in the well.
Determine the sizes of the DNA bands that would appear on an agarose gel after digestion with SciI only.
Restriction Enzyme DNA Fragment Products (8 Length, 2 Sites)
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DNA Fragment Question:Shown below is a short DNA fragment that is only 8 kb in length. This fragment has been isolated for restriction enzyme analysis.
| MlsI | PdiI | MlsI | |||||||||||||||||
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | |||||||||||
Two (2) distinct types of restriction enzyme recognition sites, MlsI and PdiI, are labeled at the top of this DNA segment.
Determine the sizes of the DNA bands that would appear on an agarose gel after digestion with MlsI only.
Restriction Enzyme Overhang Sequences (6 Choices)
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Restriction enzymes are proteins that cut DNA at specific sequences to produce fragments for further study. These enzymes are obtained from various types of bacteria and have the ability to recognize short nucleotide sequences within a larger DNA molecule.
The restriction enzyme we are focusing on is BspT104I, which is derived from the bacterium Bacillus species T104.BspT104I cuts the DNA sequence as follows: 5'-TT|CGAA-3', where the '|' indicates the cleavage site.
Based on this information, which one of the following sequences below corresponds to the overhang region of the DNA after cleavage by the restriction enzyme BspT104I?
Restriction Enzyme Cleavage Types
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Restriction enzymes are proteins that cut DNA at specific sequences to produce fragments for further study. These enzymes are obtained from various types of bacteria and have the ability to recognize short nucleotide sequences within a larger DNA molecule.
The restriction enzyme we are focusing on is BssNAI and is obtained from the bacteria Bacillus stearothermophilus NA.BssNAI cuts the DNA sequence as follows: 5'-GTA|TAC-3' where the '|' indicates the cut location.
Based on this info, can you identify the type of cut this enzyme makes?
Restriction Enzyme Overhang Types
Click to show Restriction Enzyme Overhang Types example problem
Restriction enzymes are proteins that cut DNA at specific sequences to produce fragments for further study. These enzymes are obtained from various types of bacteria and have the ability to recognize short nucleotide sequences within a larger DNA molecule.
The restriction enzyme we are focusing on is SgrDI and is obtained from the bacteria Streptomyces griseus RFL6.SgrDI cuts the DNA sequence as follows: 5'-CG|TCGACG-3' where the '|' indicates the cut location.
Based on this info, can you identify the type of cut this enzyme makes?
Palindromic Sequence Matches
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The following numbered sequences only contains half of a palindromic sequence.
Match the correct lettered sequence that would finish and replace the 'N's in the sequence to make them palindromes.
Letters will be used exactly once.
| Your Choice | Prompt | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
1.
|
||||||||||||
2.
|
||||||||||||
3.
|
||||||||||||
4.
|
Drag one of the choices below:
-
A.
T A A -
B.
A A T -
C.
T T A -
D.
A T T
RFLP Paternity Testing Results (EASY, 3 Males)
Click to show RFLP Paternity Testing Results (EASY, 3 Males) example problem
The Question
Who is the father of the child?
| Mother | ||||||||||||||||||||||||||||||
| Child | ||||||||||||||||||||||||||||||
| Male 1 | ||||||||||||||||||||||||||||||
| Male 2 | ||||||||||||||||||||||||||||||
| Male 3 | ||||||||||||||||||||||||||||||
Background
Restriction Fragment Length Polymorphism (RFLP) is a molecular biology technique used to distinguish between closely related DNA samples. It's commonly employed in paternity tests, among other applications.
Disclaimer
In actual diagnostic processes, the results of RFLP for confirming paternity are often cited to provide a 99.9% accuracy level or higher. However, no test is foolproof. Legal confirmation may involve additional procedures and evaluations to ensure the integrity and admissibility of the test.
Instructions
Use the provided DNA gel profile to determine paternity. Each band in the gel corresponds to a DNA fragment. Fragments are inherited; thus, the child's DNA will have overlapping fragments with the true father.
RFLP Paternity Testing Results (HARD, 9 Males)
Click to show RFLP Paternity Testing Results (HARD, 9 Males) example problem
The Question
Who is the father of the child?
| Mother | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Child | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 1 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 2 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 3 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 4 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 5 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 6 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 7 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 8 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 9 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Background
Restriction Fragment Length Polymorphism (RFLP) is a molecular biology technique used to distinguish between closely related DNA samples. It's commonly employed in paternity tests, among other applications.
Disclaimer
In actual diagnostic processes, the results of RFLP for confirming paternity are often cited to provide a 99.9% accuracy level or higher. However, no test is foolproof. Legal confirmation may involve additional procedures and evaluations to ensure the integrity and admissibility of the test.
Instructions
Use the provided DNA gel profile to determine paternity. Each band in the gel corresponds to a DNA fragment. Fragments are inherited; thus, the child's DNA will have overlapping fragments with the true father.
RFLP Paternity Testing Results (MEDIUM, 5 Males)
Click to show RFLP Paternity Testing Results (MEDIUM, 5 Males) example problem
The Question
Who is the father of the child?
| Mother | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Child | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 1 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 2 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 3 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 4 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Male 5 | ||||||||||||||||||||||||||||||||||||||||||||||||||
Background
Restriction Fragment Length Polymorphism (RFLP) is a molecular biology technique used to distinguish between closely related DNA samples. It's commonly employed in paternity tests, among other applications.
Disclaimer
In actual diagnostic processes, the results of RFLP for confirming paternity are often cited to provide a 99.9% accuracy level or higher. However, no test is foolproof. Legal confirmation may involve additional procedures and evaluations to ensure the integrity and admissibility of the test.
Instructions
Use the provided DNA gel profile to determine paternity. Each band in the gel corresponds to a DNA fragment. Fragments are inherited; thus, the child's DNA will have overlapping fragments with the true father.
RFLP Forensic DNA Analysis Results (EASY, 4 Suspects)
Click to show RFLP Forensic DNA Analysis Results (EASY, 4 Suspects) example problem
The Question
Which suspect left blood at the crime scene?
| Victim | ||||||||||||||||||||||||||||
| Blood | ||||||||||||||||||||||||||||
| Suspect #1 | ||||||||||||||||||||||||||||
| Suspect #2 | ||||||||||||||||||||||||||||
| Suspect #3 | ||||||||||||||||||||||||||||
| Suspect #4 | ||||||||||||||||||||||||||||
Background
Restriction Fragment Length Polymorphism (RFLP) is a molecular biology method used to differentiate between closely related DNA samples. It is often used in forensic investigations.
Disclaimer
In adherence to the principles of due process, all individuals in this exercise shall be presumed innocent until proven guilty beyond a reasonable doubt in a court of law.
Instructions
Examine the provided DNA gel profile to identify which suspect is responsible for leaving the blood sample. Each band in the gel signifies a DNA fragment. The killer's DNA will match with the blood sample found at the crime scene.
RFLP Forensic DNA Analysis Results (HARD, 9 Suspects)
Click to show RFLP Forensic DNA Analysis Results (HARD, 9 Suspects) example problem
The Question
Which suspect left blood at the crime scene?
| Victim | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Blood | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #1 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #2 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #3 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #4 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #5 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #6 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #7 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #8 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #9 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Background
Restriction Fragment Length Polymorphism (RFLP) is a molecular biology method used to differentiate between closely related DNA samples. It is often used in forensic investigations.
Disclaimer
In adherence to the principles of due process, all individuals in this exercise shall be presumed innocent until proven guilty beyond a reasonable doubt in a court of law.
Instructions
Examine the provided DNA gel profile to identify which suspect is responsible for leaving the blood sample. Each band in the gel signifies a DNA fragment. The killer's DNA will match with the blood sample found at the crime scene.
RFLP Forensic DNA Analysis Results (MEDIUM, 5 Suspects)
Click to show RFLP Forensic DNA Analysis Results (MEDIUM, 5 Suspects) example problem
The Question
Which suspect left blood at the crime scene?
| Victim | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Blood | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #1 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #2 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #3 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #4 | ||||||||||||||||||||||||||||||||||||||||||||||||||
| Suspect #5 | ||||||||||||||||||||||||||||||||||||||||||||||||||
Background
Restriction Fragment Length Polymorphism (RFLP) is a molecular biology method used to differentiate between closely related DNA samples. It is often used in forensic investigations.
Disclaimer
In adherence to the principles of due process, all individuals in this exercise shall be presumed innocent until proven guilty beyond a reasonable doubt in a court of law.
Instructions
Examine the provided DNA gel profile to identify which suspect is responsible for leaving the blood sample. Each band in the gel signifies a DNA fragment. The killer's DNA will match with the blood sample found at the crime scene.