Genetic analysis of a woman's skull discovered in the southwest 14,000 years ago China believes she is descended from an ancient population that migrated to North America from east Asia.
|A side view of an ancient skull discovered in China's Red Deer Cave. Ji, Xueping|
DNA from a 14,000-year-old skull discovered in southwest China reveals that the individual was a member of our species, Homo sapiens, with genetic ties to Native Americans' east Asian ancestors.
The cranium, which belonged to a man named Mengzi Ren, was discovered in 1989 in Red Deer Cave in China's Yunnan province. Since then, scientists have debated whether the skull belonged to a Neanderthal or Denisovan, or to a member of our species.
Bing Su of the Chinese Academy of Sciences Kunming Institute of Zoology and his colleagues have now determined that Mengzi Ren was a female H. sapiens by analyzing ancient DNA from the specimen. The team sequenced only a tiny portion of the genome, 100 million DNA bases, but this was enough to determine the individual's species-level identity.
"It was a very exciting moment," Su says. "It's difficult to find ancient DNA in a sample like this." We discovered ancient DNA that we could sequence after three years of trying to extract DNA from around 100 spots on the cranium."
The team discovered genetic similarities between the individual and living people of East Asian ancestry, as well as Native Americans, by comparing Mengzi Ren's genome with ancient genomes from around the world. This suggests that Mengzi Ren was related to ancient East Asian populations who contributed to Native American ancestry.
Analyzing the DNA of living people has previously revealed Native Americans' east Asian ancestry.
"This is the first time we've sequenced an ancient east Asian genome from the time when people were migrating into America, helping to confirm Native Americans' east Asian ancestry," Su says.
Based on their genetic findings, the researchers believe that some of these Native American ancestors may have traveled north along the coast of present-day eastern China and the Japanese islands before crossing into America from Siberia.
"This work is very exciting because it shows how east Asian settlement is linked to the peopling of America," says Tábita Hünemeier of Spain's Institute of Evolutionary Biology.
She goes on to say that there is evidence that some of the original inhabitants of the Americas dispersed westwards back into east Asia. "This could be [another] explanation for Mengzi Ren's ancestry and ancient Native Americans," she says.
Reference: Current Biology, DOI: 10.1016/j.cub.2022.06.016