So many white people have bought into consumer genetic testing that it’s now possible for law enforcement agencies to use genetic data to hunt down virtually anyone of European descent — even if they’ve never spit in a trendy tube themselves — by tracking their distant relatives who have already shared their results from companies like 23andMe and Ancestry.com.

According to a study published in the academic journal Science, it’s not all that difficult to find someone in the U.S. based on existing, easily accessible ancestral data. And it’s all thanks to the 15 million people who have voluntarily submitted to the autosomal genetic tests. After all, that’s how police found and finally arrested the so-called “Golden State Killer,” Joseph James DeAngelo, in April — by matching DNA from decades-old crime scenes to the online DNA database run by GEDmatch, a Florida-based, open-access genealogy website. Through that new, inexpensive technology, the Sacramento County Sheriff’s Department got a sense of DeAngelo’s family tree and narrowed down their suspect profile to an older, 5-foot-11-inch white male.

Since then, at least 13 cases have been reportedly solved through such long-range familial searches, according to the study, which was published Thursday.

With that in mind, the researchers analyzed a dataset of 1.28 million people who used a genetic testing kit with a direct-to-consumer provider, and found that about 60 percent of searches for people of European descent resulted in a third cousin or closer match, otherwise indicating a shared ancestor that would offer a person’s identification upon further research.