New Genetic Analysis Confirms Inbreeding between Humans and Neanderthals

A new genetic technique shows that humans interbred with Neanderthals. The method used in the latest research could help understand the evolution of other organisms.

About 400,000 years ago, Neanderthals separated from the primate line that gave rise to modern humans. The group then moved to Eurasia and completely disappeared from the world about 30,000 years back. Other studies have shown that Neanderthals might have lived near the Arctic Circle around 31,000 to 34,000 years ago.

Previous research has shown that Europeans and Asians have some Neanderthal genes in their genome. But, how were these genes transferred?

 One theory is that humans that moved out of Africa interbred with Neanderthals. Another theory is that both Neanderthals and humans share a common ancestor and so have some common genes.

The present study by researchers at University of Edinburgh and colleagues was based on statistical modeling. Their research supports the idea that human had sex with Neanderthals.

"We did a bunch of math to compute the likelihood of two different scenarios," said Laurent Frantz, study co-author and evolutionary biologist at Wageningen University in the Netherlands, according to the Verge. "We were able to do that by dividing the genome in small blocks of equal lengths from which we inferred genealogy."

Researchers said that the new method allows them to say that humans interbred with Neanderthals with a high degree of certainty.

According to the team, the latest genetic technique can be used to study the evolution of other organisms with limited genetic sample. The team had actually developed the method to study insect populations of Europe and rare species of pigs in South East Asia.

"This work is important because it closes a hole in the argument about whether Neanderthals interbred with humans. And the method can be applied to understanding the evolutionary history of other organisms, including endangered species," said Mark Johnston, Editor-in-Chief of the journal Genetics, according to a news release.

The study is published in the journal Genetics.