By Gordon Hull
A couple of weeks ago, in a post on Theranos, which has been developing a new – and very fast and cheap – technique for blood-testing, I mentioned the woes of 23andMe.com, a site which originally offered direct to consumer genetic testing, before the FDA shut it down for any medical claims (the FDA letter is here). As 23andMe put it (in a pre-shutdown version of its website), customers might “gain insight into your traits, from baldness to muscle performance. Discover risk factors for 97 diseases. Know your predicted response to drugs, from blood thinners to coffee. And uncover your ancestral origin.” That sort of claim, and its dubious scientific basis, was the basis of the FDA’s shutdown order, which also expressed concern about false positives and the difficulty in understanding negative results in isolation. In this, the FDA was echoing concerns of bioethicists, who have generally been alarmed about the spread of genetic testing outside of a clinical context. As a 2011 piece summarized the concerns, the lack of regulatory oversight of these practices, which trade upon the public’s fear of cancer and limited understanding of genetics, creates potential problems with inappropriate referrals, misinterpretation of results, excessive anxiety about positives, false reassurances about negatives, and even the confusion between diagnostic genetic variants and surrogate genetic markers (which account for very little risk).
