Deborah Bolnick Part of Research Team Confirming Link Between Earliest Americans and Modern Native Americans
Posted: May 16, 2014
Assistant Professor Deborah Bolnick was among the team of international researchers who found that the ancient remains of a teenage girl discovered in an underwater Mexican cave establish a definitive link between the earliest Americans and modern Native Americans. Bolnick analyzed DNA from the remains simultaneously with independent researchers at Washington State University and the University of Illinois at Urbana-Champaign. The findings have major implications for our understanding of the origins of the Western Hemisphere’s first people and their relationship to contemporary Native Americans.
Dr. Bolnick's statement from Wednesday's Science press briefing:
To investigate the ancestry of the Hoyo Negro girl and her genetic affinities to worldwide human populations, we carried out analysis of the Hoyo Negro Paleoamerican in three independent laboratories specializing in ancient DNA research. Brian Kemp first extracted DNA from one of the girl’s teeth at Washington State University, and then I extracted DNA from the tooth in my laboratory at the University of Texas at Austin. We both analyzed part of the girl’s mitochondrial DNA, which is maternally inherited (passed down from mother to child). We each found that she belonged to mitochondrial haplogroup D1, a genetic lineage that occurs only in the Americas. Ripan Malhi’s laboratory at the University of Illinois at Urbana-Champaign confirmed this result by targeting her complete mitochondrial genome using some of the DNA extracted at Washington State University.
Haplogroup D1 is derived from an Asian lineage but is only found in the Americas today. This lineage is found throughout North, Central, and South America; 11% of Native Americans exhibit haplogroup D1. It is especially common in some South American populations, with 29% of indigenous peoples in Chile and Argentina exhibiting this genetic lineage. Geneticists think that this lineage arose in Beringia after the ancient Beringian population became separated from other Asian populations. Previous studies have also suggested that it was one of the lineages present in the first people to settle the Americas.
Our results support this hypothesis. The presence of this lineage in the 12,000 to 13,000 year old skeleton from Hoyo Negro indicates that this girl was maternally related to living Native Americans and traces ancestry to the same source population as modern Native Americans. Our results therefore provide no evidence for an early migration to the Americas from southeast Asia or Europe. Rather, Paleoamericans —those earliest people with the distinctive skull and facial features — could have come from Siberia too. It therefore seems more likely that differences between Paleoamericans and Native Americans today are due to evolutionary changes that occurred in Beringia and the Americas over the last 9,000 years.
The findings were also published by several national and international news sources. Here are a few of those links:
National Geographic (includes video)