This New York Times article describes the "chic" trend in at-home custom genome scans. For $399 and a little spit, the California-based company 23 and me will survey your genes, providing you a long list of supposed health predispositions and risks, in addition to genetic information about "...food preferences, eye color, athletic ability and other traits."
The prospect of being able to peek at your genes and perhaps learn a little something about your inner workings is admittedly enticing. But there are some real concerns with the type of broad-scale genetic testing that companies like 23 and me offer - concerns that the companies don't exactly address up front. First off, there's real uncertainty over whether the results you receive are "clinically valid." That is, whether the tests actually tell you what they are supposed to tell you. Many of the so-called links between genes and diseases have not been fully worked out yet. What researchers have learned thus far is that common diseases like diabetes and heart disease are caused by a genetic predisposition and important non-genetic factors: the kinds of food you eat, the amount you exercise, and the lifestyle you live. There's also the issue of test usefulness - would it really make a difference to you if you found out that your genes put you at a 4% increased risk of diabetes? The much, much bigger risk is not eating healthy and lying around on the couch.
This is not to say that genes can't make make powerful predictions about risk for disease. In some cases the answer is certainly yes. But we are in the very early stages of figuring out how genes and our environment - together - shape our health. One needs to be on guard for companies looking to make a buck off of otherwise healthy people's genetic curiosity.
There are other concerns as well - how will you receive news about a potentially life-threatening condition? Will you be falsely reassured if you are overweight but do not carry the "diabetes genes?" Was the test accurate? Could the results impact my life insurance policy? Will my family members view me differently?
And about that alleged genetic test for athletic ability? Hmmm. I'd love to see the scientific data on that one.