In a commentary appearing in this week's Nature, Stanford University's Carlos Bustamante and Francisco De La Vega, and Esteban Burchard from the University of California, San Francisco say that, to date, "medical genomics has focused almost entirely on those of European descent." Because of this, the trio says, "other ethnic groups must be studied to ensure that more people benefit." Wired's Brandon Keim says that while researchers first focused primarily on common genetic variants which are "shared by relatively large numbers of people" to explain certain phenotypic associations, increasingly they are turning their focus to rare variants in order to account for the so-called missing heritability. "Whereas common variants tend to be shared across racial and ethnic groups, rare variants seem to be group-specific," Keim adds. In a Q&A interview with the Los Angeles Times' Eryn Brown, Stanford's Bustamante says that while there has recently been "a burgeoning explosion of these [genome-wide association studies] in East Asian populations, led in part by the BGI in Shenzhen, China … the rest of the world is being left behind, and we view that as problematic." At present, he adds, "something like 96 percent of the participants in medical genomics studies are of European descent. It’s a hugely lopsided representation." Bustmante adds that the racial disparity in genomics research resembles the gender disparity in scientific research decades ago. "For a long time, people only included men in medical studies. And that was problematic," he says. "You can’t study breast cancer, for example, in [only] men." When it comes to solving this problem, the Stanford professor tells the LA Times that in order to increase public support for increasingly diversified genomics research, "we need to explain why this matters. We have an obligation and duty to explain."