Why is hair found at a crime scene not normally used for DNA typing?
If the hair has been dyed or colored, it shows a smooth uniform look. DNA can be extracted from hair so why is hair found at a crime scene not normally used for DNA typing? The recent development of mtDNA analysis has made it possible to determine perform DNA typing on a single hair.
Why is hair evidence not reliable?
Hairs from other body areas generally are not considered suitable for comparison because these other body-area hairs generally do not contain sufficient variation in their microscopic characteristics to reliably distinguish between hairs from different individuals.
Why can’t a hair shaft be used to collect an individual’s DNA?
Answer: A hair w/out the follicle and its nuclear DNA, or genetic material in its nucleus, cannot provide individual evidence. Physical examination of the hair can only yield class evidence.
What are the possible limitations of using hair as evidence in a crime scene?
A limitation of using hair as evidence from a crime scene is that hair can not be directly linked to a suspect. It is impossible to say that a hair sample came from only one specific person.
When you kiss someone their DNA stays in your mouth?
No matter how fleeting the encounter, the DNA will hang around in their mouth for at least an hour. This means that women’s saliva could contain evidence of unwanted attention in cases of assault, or even telltale signs of infidelity.
How accurate is a mouth swab DNA test?
Swabs are as accurate as blood. Epithelial cells contain exactly the same DNA as blood cells. In other words, these swab tests are more than 99.9% accurate, which is the same in case of blood samples as well.
Can a mouth swab DNA test be altered?
It’s important to remember that swab contamination can never “change” the results of a paternity test or “change the DNA.” So there’s no need to worry! If contamination occurs, the lab always catches it, and the worst that can happen is the lab will ask for samples to be collected again.