Question

Below is a DNA fingerprint for a criminal case made using RFLP analysis. From left to right the wells represent a standard, evidence from crime scene using DNA evidence from two different parts of the genome from John Smiths blood and two similar parts of the genome from Jane Jones blood.
CSi represents the DNA taken from the crime scene at two locations.
The Std. (standard) lane is used for distance length references.
What does this RFLP analysis indicate?

• A. The evidence is inconclusive.
• B. Jane Jones DNA was found at the crime scene.
• C. John Smiths DNA was found at the crime scene.
• D. Both Jane and John appear to be guilty of the crime.

Answer 1

The correct option is B Jane Jones DNA was found at the crime scene.

RFP is a technique that was invented in the 1980s with an aim to research hereditary diseases. VNTMs are used for the differentiation of DNA patterns.

The basic principle behind this technique is that the restriction endonucleases are enzymes that cut lengthy DNA into short pieces. Each restriction endonuclease targets different nucleotide sequences in a DNA strand and therefore cuts at different sites.

The distance between the cleavage sites of a certain restriction endonuclease differs between individuals. Hence, the length of the DNA fragments produced by a restriction endonuclease will differ across both individual organisms and species.

In the given question we can see that the CS1 and CS2 patterns match the samples of Janes DNA.

So, the correct option is 'Jane Jones DNA was found at the crime scene.'