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Forensic DNA Profile Analysis

More methods of VNTR analysis

1. Which of the following is NOT a part of the methods used in single locus probe analysis of VNTR regions of human DNA? Please explain the right answer.

A. DNA extraction
B. Restriction endonuclease digestion of DNA
C. Gel electrophoresis
D. Autoradiography
E. Recombinant DNA

Solution Preview

The correct answer is E. Recombinant DNA

Why is this the best answer?

Recombinant DNA is not used in forensic DNA profile analysis. See the section below for more information on the techniques that are used.

A single-locus probe of the VNTR regions of DNA uses the technique of "Southern" hybridization to analyze polymorphic regions of human DNA. The experimental steps used in a forensics laboratory for this analysis are as follows:

1. DNA extraction

DNA can be extracted from almost any human tissue. Sources of DNA found at a crime scene might include blood, semen, tissue from a deceased victim, cells in a hair follicle, and even saliva. DNA extracted from items of evidence is compared to DNA extracted from reference samples from known individuals, normally from blood.

2. Digestion of DNA with a restriction endonuclease

Extracted DNA is treated with a restriction endonuclease, which is an enzyme that will cut double stranded DNA whenever a specific DNA sequence occurs. The enzyme most commonly used for forensic DNA analysis is HaeIII, which cuts DNA at the sequence 5'-GGCC-3'.

3. Agarose gel electrophoresis

Following DNA digestion, the resulting DNA fragments are separated by size via electrophoresis in agarose gels. During electrophoresis, DNAs which are negatively charged ...

Solution Summary

This solution provides the best answer of a multiple choice question methods used in single locus probe analysis of VNTR regions of human DNA. It also provides a detailed explanation of why it is the best answer.