Question

Investigator Sheer is testifying about DNA evidence she found at the crime scene that matches the suspect on trial. The prosecutor asks Investigator Sheer to explain her conclusion that the DNA samples matched.

What would be a good explanation for her to give to the jury?

That at least 10 different points on the two samples matched
That the DNA profile matches someone with the suspect's hair color and skin tone
That she found one point that matched on the two DNA samples
That the DNA samples showed no clear points in common

Answer 1

Investigator Sheer explained that DNA matching is based on a comprehensive comparison of genetic markers, where a match of at least 10 different points signifies that the suspect's DNA is identical to the DNA found at the crime scene.

Step-by-step explanation:

Investigator Sheer can explain her conclusion that the DNA samples matched by stating that DNA analysis revealed at least 10 different points on the DNA profiles of the suspect and the evidence from the crime scene that are identical. This high number of matching points is a scientifically strong indication that the two samples come from the same individual, given the uniqueness of DNA profiles among individuals (with the exception of identical twins). The DNA profile comparison does not rely on physical traits such as hair color or skin tone, and finding only one point of match is not sufficient to conclude a match. Likewise, if there were no points in common, it would not indicate a match. Therefore, the conclusion that the DNA from the crime scene matches the suspect's DNA is based on a comprehensive analysis of multiple genetic markers.