I've been curious about what my DNA says, and went so far as to buy a 23andme kit years ago. I never sent it in, because I don't like the idea of some company retaining that kind of deeply personal data about me. It's useless to resist, though; my sister and some cousins submitted theirs, and that's enough to destroy any real sense of anonymity I might have. I don't have any particular concern; it's just one of the myriad ways that privacy no longer exists.