Showing posts with label Alaska. Show all posts
Showing posts with label Alaska. Show all posts

April 19, 2015

mtDNA of Alaskan Eskimos

AJPA DOI: 10.1002/ajpa.22750

Mitochondrial diversity of Iñupiat people from the Alaskan North Slope provides evidence for the origins of the Paleo- and Neo-Eskimo peoples 

Jennifer A. Raff et al.

ABSTRACT

Objectives:


All modern Iñupiaq speakers share a common origin, the result of a recent (∼800 YBP) and rapid trans-Arctic migration by the Neo-Eskimo Thule, who replaced the previous Paleo-Eskimo inhabitants of the region. Reduced mitochondrial haplogroup diversity in the eastern Arctic supports the archaeological hypothesis that the migration occurred in an eastward direction. We tested the hypothesis that the Alaskan North Slope served as the origin of the Neo- and Paleo-Eskimo populations further east.

Materials and Methods:

We sequenced HVR I and HVR II of the mitochondrial D-loop from 151 individuals in eight Alaska North Slope communities, and compared genetic diversity and phylogenetic relationships between the North Slope Inupiat and other Arctic populations from Siberia, the Aleutian Islands, Canada, and Greenland.

Results:

Mitochondrial lineages from the North Slope villages had a low frequency (2%) of non-Arctic maternal admixture, and all haplogroups (A2, A2a, A2b, D2a, and D4b1a–formerly known as D3) found in previously sequenced Neo- and Paleo-Eskimos and living Inuit and Eskimo peoples from across the North American Arctic. Lineages basal for each haplogroup were present in the North Slope. We also found the first occurrence of two haplogroups in contemporary North American Arctic populations: D2a, previously identified only in Aleuts and Paleo-Eskimos, and the pan-American C4.

Discussion:

Our results yield insight into the maternal population history of the Alaskan North Slope and support the hypothesis that this region served as an ancestral pool for eastward movements to Canada and Greenland, for both the Paleo-Eskimo and Neo-Eskimo populations

Link

August 28, 2014

The prehistory of New World Arctic (Raghavan et al. 2014)

Science 29 August 2014: Vol. 345 no. 6200 DOI: 10.1126/science.1255832

The genetic prehistory of the New World Arctic

Maanasa Raghavan et al.

The New World Arctic, the last region of the Americas to be populated by humans, has a relatively well-researched archaeology, but an understanding of its genetic history is lacking. We present genome-wide sequence data from ancient and present-day humans from Greenland, Arctic Canada, Alaska, Aleutian Islands, and Siberia. We show that Paleo-Eskimos (~3000 BCE to 1300 CE) represent a migration pulse into the Americas independent of both Native American and Inuit expansions. Furthermore, the genetic continuity characterizing the Paleo-Eskimo period was interrupted by the arrival of a new population, representing the ancestors of present-day Inuit, with evidence of past gene flow between these lineages. Despite periodic abandonment of major Arctic regions, a single Paleo-Eskimo metapopulation likely survived in near-isolation for more than 4000 years, only to vanish around 700 years ago.

Link