FRIDAY, July 22, 2011 (HealthDay News) -- Genetic research from Canadian scientists confirms early modern humans interbred with Neanderthals.
An international team of researchers found that some of the human X chromosome can be traced to Neanderthals and is found in non-Africans everywhere.
Neanderthals are thought to have lived until about 30,000 years ago in what is now France, Spain, Germany and Russia. Their ancestors however, left Africa long before that -- about 400,000 to 800,000 years ago. Meanwhile, early modern humans left Africa between 50,000 and 80,000 years ago.
Although Neanderthals were physically more powerful than early modern humans, they possessed the gene for language and may have even played the flute. Now, researchers confirmed what experts have long considered: the two species actually interbred. The researchers pointed out this probably happened early on at the crossroads of the Middle East.
About 10 years ago, researchers identified a piece of DNA (called a haplotype) in the human X chromosome that appeared unusual.
By 2010, when the Neanderthal genome was sequenced, the researchers compared 6,000 chromosomes from all parts of the world to the Neanderthal haplotype. The Neanderthal sequence was present in peoples across all continents, except for sub-Saharan Africa, and including Australia.
"There is little doubt that this haplotype is present because of mating with our ancestors and Neanderthals. This is a very nice result, and further analysis may help determine more details," human ancestry researcher Dr. Nick Patterson, of the Broad Institute of MIT at Harvard University said in a news release from the University of Montreal.
The study's authors noted the close association with Neanderthals probably helped early modern human survival around the world. "Variability is very important for long-term survival of a species," researcher Damian Labuda, of the University of Montreal, said in the news release. "Every addition to the genome can be enriching."
The study was published in the July issue of Molecular Biology and Evolution.
The National Human Genome Research Institute provides more information on genomics.