You can still get a lot out of DNA today. There have already been murderers apprehended because their family members agreed to undergo DNA testing even though t

You can still get a lot out of DNA today. There have already been murderers apprehended because their family members agreed to undergo DNA testing even though they didn't. IIRC it's possible in many cases to go from anonymous genome (and no other info) to a surname with a distressingly high degree of accuracy. It doesn't really involve trying to predict phenotypes or anything, it's basically just because you are distantly related with at least some people who have their names attached to DNA sequences. It becomes even easier to identify someone if you have some very limited extra information. Like, say, the postcode their sample was mailed from. My understanding is that basically the idea of an "anonymous" DNA sequence is going to quickly become meaningless, that unless the person being sampled takes extraordinary effort it will be possible to narrow down who they are. It only takes like 30-40 bits of information to uniquely identify a human.