[agotterer]

It's sort of sudo anonymized. I purchased my test in 2010. The account is tied to my email address for login. I ordered the test under just my first name to my office at the time. I also purchased a test for a friend. Other then an email address, that test isn't tied to him in any other way. So while its not impossible to tie back to someone, it's not a perfect 1:1 relationship.

[jacquesm]

That's your DNA, by definition it is not anonymized, it defines you about as good as possible. You could infer all kinds of stuff about you from your DNA. 33 bits... male, brown eyes, family member in the 3rd degree of 'x', family member to the 4 th degree of 'y' and so on.

[a_bonobo]

With the caveat that you can not predict these phenotypes with 100%:

for example, in humans it's relatively easy to predict eye colour with about 99% certainty (but only if the colour is identified as "brown", "blue", "green" - nothing complicated!), however, skin colour is harder to predict (72% correct in this paper) - https://www.sciencedirect.com/science/article/pii/S187249731...

People always assume that you can just look at the genes and immediately perfectly predict what's going on with the person in question, but a) people forget about gene/environment interaction (think about human height, only about 5% predictable using SNPs) and b) our science is simply not so far, and especially SNPs (right now the main product of 23andMe) don't predict as much as people would like them to.