Correctly identifying blood at a crime scene isn’t the easiest thing to do.
That was the case in a murder trial that Dr. Bruce McCord, professor within the Department of Chemistry and Biochemistry, served as an expert witness in. A woman was murdered shortly after she went through a divorce, and DNA from her ex-husband was found on her body. But it was hard to tell if the DNA was the result of innocent contact between the two, or if it was incriminating, and came from blood.
“The techniques that we have to detect blood aren’t so sensitive,” McCord says. When the trial completed, he went on a quest to find a better method. “There ought to be tissue-specific markers on the DNA that would be able to differentiate one type from another.”
McCord’s research into that question is part of the growing field of forensic epigenetics, which 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. They’re working to develop methods that use this area of study to identify not only the tissue type of DNA that may have been left behind at a crime scene but the age and lifestyle of the person who left it there.
McCord and his team are collaborating with the San Fransisco Police Department to start to validate their methods.
Read the Popular Science article for the full story.