Race, genes, and illness

DOES A "genetic component" cause a higher rate of premature births among black mothers? Do black people carry certain gene variants that give them weaker hearts? Do Asians have special genes that enable the drug Iressa to fight non-small cell cancer better in their lungs?

Yes, indeed, authors of several recent medical studies claim. More and more, researchers are holding out the hope that genetic differences may finally explain a good part of the troubling health disparities among races. Perhaps then, the reasoning goes, the powerful tools of molecular biology may help solve them.

This research is worth pursuing if it holds the promise to improve medical care. Still, whenever these claims arise, they deserve a tough second look. Race paired with genetics has a sordid history -- not just in Nazi Germany but also today, in the form of weakly documented evolutionary claims implying one group's superiority over another.

So far, the claims about race and medical genetics remain disturbingly fuzzy. What's meant by a "genetic component," for instance? The team at Washington University in St. Louis that studied...