Genetic Diversity of Native Americans: New Research finds evidence in genes for both prehistoric migrations and environmental adaptations.

For many years, anthropologists have asked who the first Americans were, and how they were able to settle the last major habitat open to humans. Now, a special section of the American Journal of Physical Anthropology features six new papers that use genetics to answer these questions.  The findings reported confirm that genetic diversity in contemporary Native Americans bears signatures of the past.  The authors find evidence in genes for both prehistoric migrations and adaptations to the new environment.  These papers contribute new findings related to distinct phases in the evolution of Native Americans. 

Two papers address the initial peopling of the Americas.  A team led by Dr Judith Kidd (Yale University) explored hundreds of DNA markers from people on different continents.  This team was able to detect in Native Americans signatures of Asian ancestry from Mongolia, Tibet and Siberia.   Soledad de Azevedo and colleagues (Central University of Patagonia, Argentina) examined skeletal morphology and found evidence for pre-Columbian gene flow between Native Americans and Northern Asians. 

Two more papers related patterns of Native American genetic diversity to events and processes on the American continents.  Jennifer Raff and colleagues (University of Utah) performed a large scale analysis of DNA extracted from ancient bones.  They address the period between the first peopling of the Americas and the arrival of European explores.  Their data suggests that Native Americans evolved regional gene pools soon after they settled the new land.  Afterwards, there was regional continuity with only a few large-scale population movements.  Sohini Ramachandran (Brown University) and Noah Rosenberg (University Michigan) contributed a highly original article that related genetic diversity to geoclimatic influences on the spread of agriculture.

Keith Hunley and Meghan Healy (University of New Mexico) looked at how Native Americans have absorbed European ancestry since the time of Columbus.  They see a North to South gradient of decreasing European ancestry that mimics the movement of the first Americans from the Bering Straits to Tierra del Fuego

“The papers in this special section go beyond the traditional questions of migrations into the Americas,” concluded editor Jeffrey Long.  “They look at the Native American gene pool in terms of a remarkable human saga from deep in the past until the present.  Events along the way created layers of genetic change and adaptation.”

Papers in this special section: 

  • A New Subhaplogroup of Native American Y-Chromosome From the Andes, Jota. M,  Lacerda. D, Sandoval. J, Vieira. P, Santos-Lopes. S, Bisso-Machado. R, Paixão-Cortes. V, Revollo. S, Paz-Y-Miño. C, Fujita. R, Salzano. F, Bonatto. S, Bortolini. M, Santos. F, DOI: 10.1002/ajpa.21519
  • A Test of the Influence of Continental Axes of Orientation on Patterns of Human Gene Flow, Ramachandran. S, Rosenberg. N, 10.1002/ajpa.21533
  • Ancient DNA Perspectives on American Colonization and Population History, Raff. J, Bolnick. D, Tackney. J, O’Rourke. D, 10.1002/ajpa.21594
  • Evaluating Microevolutionary Models for the Early Settlement of the New World: the Importance of Recurrent Gene Flow with Asia, Azevedo. S, Nocera. A, Paschetta. C, Castillo. L, González. M, González-José. R, 10.1002/ajpa.21564
  • New Developments in the Origins and Evolution of Native American Populations, Long. J,   Bortolini. M, 10.1002/ajpa.21620
  • Single Nucleotide Polymorphisms and Haplotypes in Native American Populations, Kidd. J, Friedlaender. F, Pakstis. A, Furtado. M, Fang. R, Wang. X, Nievergelt. C, Kidd. K, 10.1002/ajpa.21560
  • The Impact of Founder Effects, Gene Flow, and European Admixture on Native American Genetic Diversit, Hunley. K, Healy. M, 10.1002/ajpa.21506