Why Using Genetic Genealogy to Solve Crimes Could Pose Problems

Police are using a new type of DNA sleuthing, called genetic genealogy. Already the technique has caught murder and rape suspects in California and Washington. While solving the cases has given cause for celebration, the tactics used in catching the alleged culprits have many privacy and civil rights experts worried.

Closing the Golden State Killer case (SN Online: 4/29/18) and the previously unsolved double murder of a young Canadian couple (SN Online: 5/23/18) involved probing a public online database of people’s DNA and family-tree information called GEDmatch.

In a May 29 opinion piece published in the Annals of Internal Medicine, bioethicist Christine Grady and colleagues argue that police should be more transparent about how they use forensic DNA searches. Meanwhile, law professor Natalie Ram and colleagues go even further in an essay in the June 8 Science, writing that eroding limits on the use of crime-solving technology “threatens our collective civil liberties and opens the door to socially and politically unacceptable genetic surveillance.”

Here are a few key points in the debate:

Why are police using GEDmatch instead of DNA testing companies? 

If police wanted to use 23andMe or AncestryDNA to help solve crimes, they would need a clean saliva sample from a potential suspect to send to the company for testing and analysis. But crime scene DNA doesn’t come in that form, so police can’t send DNA to the companies for testing. That’s not the case with the DNA analysis service GEDmatch, to which customers can upload raw DNA data received from testing companies.

“That means the police or law enforcement investigators are equally able, if they have enough DNA to create a sufficiently complete genetic sequence, to upload that to GEDmatch” to find potential suspects, says Ram, of the University of Baltimore School of Law.

You can read more in an article by Tina Hesman Saey published in the sciencenews web site at: http://tinyurl.com/397mvf5r