[The] field of forensic epigenetics [uses] the markers that sit on top of DNA and modify it’s expression, rather than the genetic sequence itself, to gather information that could help identify a suspect in a crime. Forensic scientists and law enforcement agencies around the world think leveraging epigenetics could add key tools to the investigative arsenal.
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[B]lood cells have a different purpose in the body than skin cells do, so different proteins will appear in unique patterns in both cells to help them carry out their specific tasks. By identifying these patterns, it’s possible to differentiate between the DNA that came from blood, and the genetic coding that came from skin.
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Going forward, epigenetics might also help predict if a suspect is a smoker, if they drink heavily, or even what their diet is. All of these behaviors leave traces, and it might be possible to predict, say, if a person is a long-time vegetarian by looking at their epigenome.
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The information isn’t enough to identify a single person—epigenetic markers aren’t fingerprints, and there’s a lot scientists still don’t know about gene expression. But knowing the age range and lifestyle habits of the person that they’re looking for might help law enforcement officers narrow down a suspect pool, in cases where there isn’t a DNA match in a database.
Read full, original post: DNA evidence could soon tell cops your age, whether you smoke, and what you ate for breakfast