Wednesday, March 08, 2006

From HapMap to selection map

It was the article by Nicolas Wade in the New York Times ("Still Evolving, Human Genes Tell New Story") that alerted me to the new article in PLoS Biology by Voight et al. ("A Map of Recent Positive Selection in the Human Genome", from Jonathan Pritchard's group at the University of Chicago). I've been anticipating a list of human genes under selection for some time, and it's exciting to see this published. This paper, perhaps more than any other, marks the transition to a new and controversial era in genetics. On the positive side, we're going to learn a lot very quickly about the genetics of human differences. This will provide many benefits and engage curiosity in satisfying and useful ways.

On the other hand, the uncritical acceptance of results that are statistical in nature (and have a real possibility of being wrong) is disturbing. A recent visitor to Sarah Tishkoff's lab (Jeff Jensen, from Cornell, where he works with Aquadro and Bustamonte) gave a talk about the statistical problem of distinguishing selection from certain demographic phenomena that made me think the interpretation of selection maps is going to be extremely uncertain. It is surprising that none of those issues were addressed in Wade's article, especially so because the New York Times typically fills their science articles with quotes from others in the field. I felt the same unease a few weeks ago when watching a PBS documentary "African American Lives," in which famous African-Americans were given overly specific information about their ancestry without appropriate statistical disclaimers.

I suppose that we will all be talking a lot more about selection and race with my friends who are not geneticists, and putting a lot more population genetics into my graduate genetics course. Clearly, the idea that population genetics is passé is now passé.