PHILADELPHIA -- Over many generations, people living in the high-altitude regions of the Andes or on the Tibetan Plateau have adapted to life in low-oxygen conditions. Living with such a distinct and powerful selective pressure has made these populations a textbook example of evolution in action, but exactly how their genes convey a survival advantage remains an open question. Now, a University of Pennsylvania team has made new inroads to answering this question with the first genome-wide study of high-altitude adaptations within the third major population to possess them: the Amhara people of the Ethiopian Highlands.
Surprisingly, all three groups' adaptations appear to involve different genetic mutations, an example of convergent evolution.
"These three groups took different genetic approaches to solving the same problem," said senior author Sarah Tishkoff, a Penn Integrates Knowledge professor with appointments in the genetics department in Penn's Perelman School of Medicine and the biology department in the School of Arts and Sciences.
In addition to Tishkoff, the research was led by Laura B. Scheinfeldt, a research scientist in the genetics department at the Perelman medical school. Other members of the genetics department who contributed to the research are Sameer Soi, Simon Thompson, Alessia Ranciaro, William Beggs, Charla Lambert and Joseph P. Jarvis.
The Penn team collaborated with Dawit Wolde Meskel, Dawit Abate and Gurja Belay of the Department of Biology of Addis Ababa University.
Their research was published today in the journal Genome Biology.
One of the guiding principles behind evolution is natural selection; the more an organism is suited to its environment, the more likely it is to survive and pass on its genes. In high-altitude environments, oxygen concentration is low, a condition that can rapidly sicken even kill individuals who are not acclimated.
|Contact: Evan Lerner|
University of Pennsylvania