DNA family history kits from Ancestry.com and 23andMe were popular gifts the past two Christmases. They cost around $100. You spit in a tube, and in a few weeks, you'll get your DNA data so that you can discover your family's history. Possibly finding
relatives from the 1700s, Sounds cool, but in the past couple of months we've learned, it's kinda scary.

"The main drawback with these DNA kits is privacy," Tiffany Li, an attorney and fellow at Yale University and someone who's concerned that practically everyone in the country has their genetic data posted on a website for anyone to see, said. "People might not realize that they're giving up their genetic privacy when they use DNA profiling websites. Not only that, but you're giving up the genetic privacy of basically everybody in your biological family."

It's how police in California located the alleged Golden State Killer who had evaded police for over 40 years. Detectives had some of his DNA from one of the old crime scenes, but since Joseph DeAngelo had never been arrested, his DNA had never been
collected and put in the DNA database police use to find and convict perpetrators. But one of his third cousins used one of these kits, then searched a public database for family members.

"They just looked up their DNA, they took the DNA profiles, checked with the samples they had and they found a match,” Li said.

Police used the website GEDMatch where people upload the DNA data to find family members who had used ancestry.com, 23andme or similar kits. It took four months of tracing family trees, but police eventually zeroed in on the former police officer.

Officers staked out his residence and then retrieved something he had thrown away that contained his DNA. DeAngelo was arrested in April.

Li pointed out that we still don’t know the extent police went about accessing the database and told me detectives would not have to create a fake account to submit the DNA data captured at the crime scene.

“Really, anyone could have gotten into this database,” she said.

It was good in this case, but has the potential to be bad if your most personal information falls into the wrong hands.

"I think that classic response, that you shouldn't care if you don't have anything to hide, that's kind of beside the point right?" Li added.

Li says, it's probably too late to say 'don't use them', because everyone has a relative who's submitted DNA information for the entire family. Just be aware that we're all giving up entirely too much information about ourselves.