Federal investigators looking to solve crimes can find a DNA match for a relative as close as a third cousin (connected by a great-great grandparent) to more than half of Americans by accessing genealogy databases. Yaniv Erlich, chief science officer at DNA testing company MyHeritage, came to that conclusion after analyzing more than 1.28 million DNA profiles, reports BuzzFeed. The FBI actually has access to 2.2 million profiles: 1.2 million from open-source site GEDmatch, and more than 1 million from Family Tree DNA, one of the largest private genetic testing firms. That connection was only revealed by BuzzFeed this week, though the company began allowing FBI access months ago. President Bennett Greenspan defended the decision, but apologized to customers "for not having handled our communication with you as we should have."
"It comes into deep conflict with what consumer expectations are," John Verdi of the Future of Privacy Forum tells BuzzFeed. "[Customers] don't sign up for genetic testing to become subject to wide ranging FBI criminal searches." Though Ancestry.com, 23andMe, and MyHeritage only provide information to law enforcement with a warrant or subpoena, Erlich predicts it will be just a few years before the FBI can assess DNA profiles for 5% of the US population, or about 7 million people. At that point, he says the FBI could link almost every American of European descent to a second cousin. For now, Americans with mostly Northern European ancestry are 30% more likely than those with mostly sub-Saharan ancestry to be identified through third cousin, a finding attributed to the popularity of at-home test kits among whites. Knowable digs into the privacy concerns. (The suspected Golden State Killer was found through a distant cousin.)