A new study shows that 9% of humans today carry Neanderthal genes because our ancestors were all about that swirl life 50,000 years ago.
“It’s in the Middle East, it’s in Europe, it’s in Eurasia, it’s in America, it’s in Australia,” study researcher Damian Labuda of the University of Montreal told LiveScience. “This one event which led to this on the human X chromosome has to occur very early after modern man left Africa.”
Early humans and Neanderthals (Homo neanderthalenis) co-existed, and researchers have long searched for evidence that the two groups mated.
Labuda got his first sign of the interbreeding about a decade ago when he discovered a snippet of DNA on the X chromosome found only in non-Africans and whose origin was unknown. (X chromosomes are sex chromosomes; women have two and men have one, paired with a Y chromosome.)
But until 2010 the group didn’t have anything to compare the snippet with. That year, the Neanderthal genome was sequenced, and a team of researchers (not including Labuda) reported in the journal Science that between 1 and 4 percent of the genome of some modern humans hails from Neanderthals, stocky hominids who lived between 130,000 and 30,000 years ago.
That 2010 study used DNA extracted from Neanderthal bones found in Croatia. With the new availability of a partial Neanderthal gene sequence from Croatia, Labuda and his team had something to compare their mysterious X chromosome fragment with.
Using DNA from 6,092 modern X chromosomes from every continent, the researchers found that the modern-day fragment matches one found in the Neanderthal genome.
Hmmm… So we’ve always been fans of interracial dating?