Rapid spread of beneficial mutations relatively rare
Humans probably didn’t get swept up in evolution.
Scientists have favored a model of evolution in which beneficial gene mutations quickly and dramatically sweep through a population due to the evolutionary advantages they confer. Such mutations would become nearly universal in a population. But this selective sweep model may not be accurate for humans, a new study indicates. Human evolution likely followed a more subtle and complicated path, say population geneticists Molly Przeworski of the University of Chicago and Guy Sella of Hebrew University of Jerusalem and colleagues.
Computational analysis of 179 genomes belonging to people from Europe, Asia and Africa reveal that selective sweeps have been rare in human evolution, the researchers report in the Feb. 18 Science.
“I’m convinced,” says Andrew Clark, a population geneticist at Cornell University. Clark was among the first to find evidence that selective sweeps can shape