Saturday, December 7, 2019

Shaking Hands Transfers DNA to Things You've Never Touched

a photo of two chess players shaking hands

The fact that DNA is transferred from a handshake between two people is a given, but DNA appearing on objects and surfaces that a person didn't even touch according to new studies. This is pretty interesting discovery because this will cause crime scene investigators to consider DNA transfer when swabbing areas of a crime scene and determining suspects. Cynthia Cale, a forensic scientist, had previously found that shaking someone's hand for 2 minutes can transfer a persons DNA to an object by way of another person. The only issue with this discovery is that it is a little bit unrealistic because a 2 minute handshake would just be too awkward. However, she did another study and narrowed it down to a 10 second handshake. This is still a pretty awkward handshake, but the DNA is still able to be transferred during this very short time frame. Cale did a study to simulate a crime scene. She had two people shake hands for 10 seconds, then she had one of those people grab a knife. It was found that a majority of the DNA found on the knife was from the person that wasn't even touching the knife. I find this to be extremely interesting because there could potentially be discrepancies in crime scene investigation, and this could complicate a detectives ability to investigate a crime.

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  1. This idea kind of scares me, after all we meet a lot of people during our lives especially when we start going into professional settings. Who's to say we won't shake the hand of a criminal and get sent to prison? Now I know that it is unlikely and kind of silly to think that, but apparently that is something that can happen. I would love to read more about this situation, and if this will make police and detectives have to change there investigation procedure.

  2. DNA evidence is already considered circumstantial, but knowing about this detail will hopefully make it easier to eliminate suspects. Knowing that transfers can come from other people may clear innocent people rather than incriminate them.