Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=199379
Story Retrieval Date: 5/23/2013 9:55:45 AM CST
Could a remote, mountainous region in southern Siberia be the genetic source from whence Native Americans sprung?
A team of anthropologists from the University of Pennsylvania has found unique genetic mutations shared between the two populations that indicate a common ancestry.
The study, recently published in the American Journal of Human Genetics, shows the genetic link between Native Americans and a population of the southern Altai region in Siberia.
The research reinforces previous genetic links to Siberia and offers a “high-resolution picture to work up until this point” in genetic and anthropological research, said Theodore Schurr, one of the study’s authors and an associate professor in Penn’s department of anthropology.
The Altai Republic, a federal subject of Russia, straddles the borders of Mongolia, China and Kazakhstan. “[I]t’s a place that people have been coming and going for thousands and thousands of years,” Schurr said.
“It’s strengthening the connection and isolating geographically the original ancestral group,” said Erin Waxenbaum, a lecturer in the department of anthropology at Northwestern University.
Waxenbaum said that craniometric analysis, or skull analysis, along with other anthropological tools were used in the past to show strong correlation to modern day and past populations of Native Americans and Asian groups. “This study allows us to be more specific,” she said.
For many years, the two groups have been associated by the assumption that Asians migrated to the Americas via a land bridge. Now the Bering Strait separates the two landmasses that are part of Russia and Alaska. Research from the study estimated genetic divergence between southern Altaian ancestors and Native Americans occurred about 13,000 to 14,000 years ago, correlating with the idea that people began migrating 15,000 to 20,000 years ago.
Schurr’s team worked in collaboration with Ludmila Osipova of the Institute of Cytology and Genetics in Russia and researched the founding lineages to Native American populations by looking at genetic variations in Altaian populations. Mitochondrial DNA, which is maternally inherited, and Y chromosome DNA, which is passed down from fathers to sons were examined.
Many Altai samples were taken for DNA analysis. “We’re using hundreds of markers to find these genetic regions,” said Schurr. “Most [previous studies] are using a fewer number. The mutation region we get is much larger,” offering a clearer picture of divergence, he said.
Southern Altaians, were pinpointed as the specific population sharing a genetic lineage with Native Americans. The southern cultural traditions shares “greater affinities with Mongolians and Central Asians than they do with northern Altaians,” the study found.
Y chromosome DNA revealed a unique mutation in a lineage shared by Native Americans and southern Altaians. The mitochondrial DNA from maternal lines also showed genetic similarities to founder peoples in North America.
Shurr said he is interested in pursuing further research using high-resolution methods. Although the fieldwork is demanding and involves going to remote locations, Schurr said it’s worth it.
“It’s a very rewarding and enriching experience to understand their ancestry and heritage,” he said. “We hope to work more extensively in Russia and Siberia in the near future to do work with other types of groups similar in genetic variation.”