To understand how the native people of the Tibetan plateau have adapted to their extreme low-oxygen environment, several research teams are comparing the genetic makeup of these mountain dwellers to that of the lowland Han Chinese. Chinese, British, and American researchers recently reported in the journals Science and PNAS that the two populations have strong differences in EPAS1, a gene involved in response to low oxygen. Scientists speculate that Tibetans have evolved a unique array of genetic adaptations in a relatively short period of evolutionary time, equipping them to thrive where most others cannot.