I would argue, though, that 23 & me has a bigger marketing problem than scientific problem. In fact, I don’t think that the typical consumer of 23 & me’s products cares at all about the nuances of the science — what the big difference is between causation and correlation, how immature the research is at this point, etc. From the average consumer perspective, the data is “good enough” (note: I don’t believe this to be true myself — I just think that the typical consumer won’t make the distinction). Especially when you see luminaries like Sergei Brin making significant life choices and investments based on these very same markers (http://www.wired.com/magazine/2010/06/ff_sergeys_search/all/1), I think the science issue is relatively less important.

Put another way, my guess is that very few people see the service, get interested, and then say “wait, I’m not going to spend $5/month — the science is bad.” Rather, I think that there are not enough people getting to that purchase point to begin with – and that’s a market-size / marketing problem.

If I were 23 & me, I would change up my marketing — focusing on the heritage and ancestry issues more than the disease markers.