Police in California made headlines this spring when they charged a former police officer with being the Golden State Killer, a man who allegedly committed a series of notorious rapes and murders in the 1970s and '80s.
Authorities revealed they used DNA from a publicly available genealogy website to crack the case.
Since then, police around the country have started doing the same sort of thing to solve other cold cases.
That prompted Yaniv Erlich, the chief science officer at the Israeli companyMyHeritage, to investigate just how easy it is to use public genealogy databases to track down people.
"We wanted to quantify how powerful this technique is to identify individuals," Erlich says. So he and his colleagues analyzed the genomes of 1.28 million people in the company's database.