Research finds clues about Interbreeding among Ancient Humans and Denisovans

Research finds clues about Interbreeding among Ancient Humans and Denisovans

A new study conducted by researchers at the University of Washington has found evidence of interbreeding between mysterious Denisovans and ancient human race. The research team found two distinct episodes of intermixing during genome-analysis of modern humans and Denisovans. For the current study, the research team sequenced genome from 5,600 individuals from Europe, Asia, America, and Oceania and compared them to the Denisovan genome.

After detailed genome analysis, the research team found that genomes of two groups of modern humans with Denisovan ancestry - individuals from Oceania and individuals from East Asia - are uniquely different, indicating that there were two separate episodes of Denisovan admixture.

Talking about the research project, Sharon Browning, a research professor at University of Washington said, "What was known already was that Oceanian individuals, notably Papuan individuals, have significant amounts of Denisovan ancestry. The genomes of modern Papuan individuals contain approximately 5 per cent Denisovan ancestry." Denisovan ancestry is present to a lesser degree throughout Asia. Researchers also suggest that the current Denisovan ancestry found in Asia could be due to migration from Oceania over time.

Earlier research conducted in year 2011 by Stanford University analyzed the genome of Denisovans and Neanderthals in search for immunity markers. Some individuals or races are better able to deal with infections and diseases and the secret lies in the genetic difference among the races. Detailed study results have been published in the journal Cell.

The current research has found a separate instance of genome from Denisovan ancestry that is not present in the South Asians and Papuans. So, this raises possibility of intermixing at two separate times. This Denisovan ancestry in East Asians seems to be something they acquired themselves, the research paper informed.

"This Denisovan ancestry in East Asians seems to be something they acquired themselves," Browning added.

A report published by Inquistr added, “There’s one beneficial gene modern man inherited from Denisovans. Rasmus Nielsen of the University of California Berkeley reported that modern Tibetans could live in an altitude of 4,000 meters because of their EPA1 gene. This gene prevents blood thickening and helps them live in extraordinary conditions.”

The research paper further informed….

Researchers found that the Denisovan genome is more closely related to the modern East Asian population than to modern Papuans. "We analysed all of the genomes searching for sections of DNA that looked like they came from Denisovans," said Browning. "When we compared pieces of DNA from the Papuans against the Denisovan genome, many sequences were similar enough to declare a match, but some of the DNA sequences in the East Asians, notably Han Chinese, Chinese Dai, and Japanese, were a much closer match with the Denisovan," she said.

What is known about Denisovan ancestry comes from a single set of archaic human fossils found in the Altai mountains in Siberia. That individual's genome was published in 2010, and other researchers quickly identified segments of Denisovan ancestry in several modern-day populations, most significantly with individuals from Oceania but also in East and South Asians. "The assumption is that admixing with Denisovans occurred fairly quickly after humans moved out of Africa, around 50,000 years ago, but we do not know where in terms of location," Browning said.

Perhaps the ancestors of Oceanians admixed with a southern group of Denisovans while the ancestors of East Asians admixed with a northern group. Researchers plan on studying more Asian populations and others throughout the world, including Native Americans and Africans.