![Click to enlarge Inuit Village](/image/s18/365424/Igloos.jpg)
© UC BerkeleySeals and walruses were part of the traditional diet of the Inuit, as seen in this illustration of a native village on Canada’s Baffin Island, from the book Arctic Researches and Life Among the Esquimaux (1865) by Charles Francis Hall.
In the Arctic, the Inuits have adapted to severe cold and a predominantly seafood diet. After the first population genomic analysis of the Greenland Inuits (
Fumagalli, Moltke et al.2015, Science), a region in the genome containing two genes has now been scrutinized by scientists: TBX15 and WARS2.
This region is thought to be central to cold adaptation by generating heat from a specific type of body fat, and was earlier found to be a candidate for adaptation in the Inuits.Now, a team of scientists led by Fernando Racimo, Rasmus Nielsen
et al. have followed up on the first natural selection study in Inuits to trace back the origins of these adaptations.
To perform the study, they used the genomic data from nearly 200 Greenlandic Inuits and compared this to the 1000 Genomes Project and ancient hominid DNA from Neanderthals and Denisovans. The results, published in the advanced online edition of Molecular Biology and Evolution, provide convincing evidence that the Inuit variant of the TBX15/WARS2 region first came into
modern humans from an archaic hominid population, likely related to the Denisovans.
"The Inuit DNA sequence in this region matches very well with the Denisovan genome, and it is highly differentiated from other present-day human sequences, though we can't discard the possibility that the variant was introduced from another archaic group whose genomes we haven't sampled yet." - said Fernando Racimo, lead author of the study.
Comment: Siberia already being clobbered with snow - portends harsh U.S. winter ahead