More interbreeding may explain higher level of Neandertal DNA compared with Europeans
Hermann Schaaffhausen/Wikimedia Commons
East Asians got a double dose of Neandertal ancestry. That’s the conclusion of two new studies seeking to explain why East Asians inherited 15 to 30 percent more Neandertal DNA than Europeans did. The results appear in the March 5 American Journal of Human Genetics.
Recent research has suggested that Neandertal DNA is slightly detrimental to modern humans, making some people more prone to certain diseases, for example (SN: 3/8/14, p.12).
Natural selection should weed out the harmful stuff, but selection may have been less efficient at jettisoning Neandertal DNA from East Asians because they had a smaller founding population than Europeans did, one hypothesis suggests. Smaller founding populations make it more likely that genes, even harmful ones, might be inherited by chance.
An alternative idea holds that European ancestors bred