Although the last Neanderthal died tens of thousands of years ago, their effects in our DNA is still being felt today. A new genetic study, revealed that certain traits in modern humans, such as height and schizophrenia risk, were inherited from Neanderthal genes.
Although previous studies determined that we only contain about 2 percent of Neanderthal DNA in our own, until now it’s been difficult to determine their effect on our gene expression. But now, researchers think they finally have an answer, and it seems that this ancient remnant is much more important than we thought.
“Hybridisation between modern humans and Neanderthals increased genomic complexity”, said Joshua Akey, geneticist from the University of Washington. “Hybridisation wasn’t just something that happened 50,000 years ago, that we don’t have to worry about anymore. Those little bits and pieces, our Neanderthal relics, are influencing gene expression in pervasive and important ways”.
While previous studies have found correlations between these genes and some modern traits like our metabolism, depression, certain skin and blood conditions and some more, there wasn’t ever a biological reason to explain this link. Last year, a team from Montreal found out that human-Neanderthal breeding, is probably part responsible for the way our immune systems behave today.
But now, Akey’s team have managed to find where these variances are in the human genome, and using this location, they’ve found biological evidence to support the fact that Neanderthal and Human DNA genes behave differently.
“We carry a lot of the Neanderthal genome in scattered bits and pieces among individuals today, and if we understand the Neanderthal genome and its function better, then we’ll understand the human genome and its function better”, told Akey to Stephan Kozub at The Verge.
The parts with lowest expression of Neanderthal genes, according to the research, are the brain and the testes, proving that these regions suffered a faster evolution since our human ancestors diverged from Neanderthals about 700 000 years ago.
Still, further study is needed to find out how many genes there are, influenced by the Neanderthal DNA, and what are the physical results of them.
The study has been published in Cell.