July 4, 2013
New Genetic Advances Tie Living Natives To Ancient Remains
Brett Smith for redOrbit.com - Your Universe Online
When Europeans began to colonize the Americas, male settlers sporadically began having children with native females.
This mixing of bloodlines would have made tracing today's native ancestries difficult several years ago, but new advances in the sequencing of mitochondrial DNA have allowed researchers to draw a direct line between someone living today and Native American remains thousands of years old.
According to a new report in PLoS ONE, a team of researchers from the US and Canada used mitochondrial DNA, which mothers pass to their children, to trace three maternal lineages from ancient times into the modern day.
The study included the mitochondrial genomes in four ancient and three living individuals from northern British Columbia, Canada. The Tsimshian, Haida and Nisga'a people have all lived in this region for countless generations; however, until this study, nothing has directly connected the current inhabitants to nearby archeological sites that are 5,000 to 6,000 years old.
"Having a DNA link showing direct maternal ancestry dating back at least 5,000 years is huge as far as helping the Metlakatla prove that this territory was theirs over the millennia," said study co-author Barbara Petzelt, referring to her Tsimshian-speaking Metlakatla community.
"This is the beginning of the golden era for ancient DNA research because we can do so much now that we couldn't do a few years ago because of advances in sequencing technologies," said co-author Ripan Malhi, a geneticist and anthropologist from University of Illinois. "We're just starting to get an idea of the mitogenomic diversity in the Americas, in the living individuals as well as the ancient individuals."
At one archeological site on the Lucy Islands, study researchers found human remains and remnants of a house structure dating between 5,300 and 6,400 years old. A DNA analysis of the remains of one young adult female, who lived about 5,500 years ago, found that her mitogenome could be traced to another female found on Dodge Island, about 10 miles away. The Dodge Island female's remains were about 2,500 years old. This mitogenomic line was also traced to a modern day study participant, making a direct maternal connection among the three individuals.
Three other study participants were also linked to another individual found on Dodge Island who lived about 5,000 years ago through a specific mitochondrial DNA sequence. The researchers noted these findings denote a long period of stability for these early Americans.
"Archaeology is one important source of information about the past, and oral traditions give us a lot of verifiable information about the past cultural events and patterns," said co-author David Archer, an anthropology professor at Northwest Community College in Canada. "But the genetic information is something that is immediately recognizable."
"If somebody is told that their DNA links to somebody who was present 2,500 years ago and also to someone who was present 5,500 years ago, you can summarize that in a sentence and it's very easily understood and it's exciting," Archer said.
The study's researchers and participants alike said they were enthusiastic about their productive collaboration.
"I believe this is really a unique collaboration," said Joycelynn Mitchell, a Metakatla co-author and participant in the study. "It's very exciting to be able to have scientific proof that corroborates what our ancestors have been telling us for generations. It's very amazing how fast technology is moving to be able to prove this kind of link with our past."