People of European and Asian descent today retain Neanderthal DNA that may affect their hair, skin, fertility, predisposition to certain diseases and possibly other characteristics, a new study in the journal Nature suggests.
The genetic material inherited from Neanderthals combined with that of humans when the two species interbred 40,000 to 80,000 years ago, the study holds. The research further supports that indigenous Africans possess little or no Neanderthal DNA because their ancestors did not breed with Neanderthals, which lived in Europe and Asia.
It now appears that mating between the two species was much more prevalent than was previously suspected.
Some genetic mutations introduced by Neanderthals were not beneficial to humans. Neanderthals' contribution to modern DNA was partially removed by natural selection over time.
"Given the large amount of Neanderthal alleles (gene variants) that were swept away by selection, we think that there was a larger fraction of Neanderthal ancestry initially," lead author Sriram Sankararaman explained to Discovery News, adding that "we think that this ancestry was reduced by a third."