Origin: A Genetic History of the Americas

complete population replacement of the Tuniit (as the Dorset are referred to
in the Eastern Arctic).
But the story was incomplete. The information had been gathered from a
single Paleo-Inuit whole genome, and other temporal and geographic gaps
in the Arctic’s genetic puzzle still existed. In 2014, Maanasa Raghavan
(currently an assistant professor in the Department of Genetics at the
University of Chicago) and her colleagues published an extensive study of
ancient individuals from Siberia, Canada, and Greenland (10). The
geneticists were able to obtain mitochondrial genomes and low-coverage
whole genomes from a number of Paleo-Inuit individuals, from Thule and
Siberian Birnirk individuals, and from Norse individuals in Greenland.
Analyses of these mitochondrial lineages confirmed that haplogroups A2a,
A2b, and D4 were found in ancestral Inuit while, haplogroup D2a was
found in all Paleo-Inuit individuals. Analyses of whole genomes showed
that the ancestral Inuit and Paleo-Inuit were indeed different groups of
people. They appeared to have experienced gene flow with each other in the
distant past, most likely when ancestors from both groups were still in
Siberia.
However, almost nothing was known about the genetic variation of the
ancient and contemporary peoples in another region that could also have
been a candidate for the origins of ancestral Inuit culture: the Alaskan North
Slope, the place where we were sampling the remains of ancient Iñupiat
ancestors at Nuvuk.
The Utqiaġvik community was supportive of the project and the
questions we were trying to answer. One elder suggested testing DNA from
the contemporary inhabitants in order to better understand their history.
This was an exciting development, and Dennis O’Rourke’s former graduate
student Geoff Hayes (now a professor at Northwestern University) turned
this into a project called the Genetic Analysis of the Alaskan North Slope
(GEANS). I was also fortunate enough to be involved in this project, and in
2015 we published the analysis of mitochondrial DNA from 137
contemporary Iñupiat individuals across the Alaskan North Slope. These
mitochondrial linages showed us that while most people belonged to
lineages common among Inuit elsewhere, the villages on the North Slope
did indeed contain a few instances of mitochondrial lineages atypical for
Inuit peoples (11). For example, haplogroup D2a, which has only