While it’s fun to submit DNA to a testing service to learn you might be 10 percent Nigerian, Norwegian, or Native American, these tests sometimes lead to unforeseen or unwanted consequences, and there are serious privacy issues at stake—after all, we’re handing off our entire genetic identities.
There’s little profit in charging $60–$100 to analyze DNA to report on ethnicity. The real profit potential lies in selling all the genetic data they are scooping up.
Most DNA ancestry companies ask customers if they wish to participate in affiliated research projects. Because most of us want to help find cures for devastating diseases like cancer, Alzheimer’s, and Parkinson’s, opt-in rates are high—23andMe says 80 percent of its customers do so.
These companies share de-identified data—they remove your name and other details. If you opt in but later change your mind, all the companies make it fairly easy to notify them you want out; there’s usually a page under account settings, or you can send a message to a help desk. But they won’t retrieve your genetic info from projects already begun...