The genetic history of Greenlandic-European contact

Ryan K Waples,Aviaja L Hauptmann,Inge Seiding,Emil Jørsboe,Marit E Jørgensen,Niels Grarup,Mette K Andersen,Christina V.L Larsen,Peter Bjerregaard,Garrett Hellenthal,Torben Hansen,Anders Albrechtsen,Ida Moltke

doi:10.1016/j.cub.2021.02.041

Abstract

SUMMARYThe Inuit ancestors of the Greenlandic people arrived in Greenland close to 1,000 years ago.1 Since then, Europeans from many different countries have been present in Greenland. Consequently, the present-day Greenlandic population has ~25% of its genetic ancestry from Europe.2 In this study, we investigated to what extent different European countries have contributed to this genetic ancestry. We combined dense SNP chip data from 3,972 Greenlanders and 8,275 Europeans from 14 countries and inferred the ancestry contribution from each of these 14 countries using haplotype-based methods. Due to the rapid increase in population size in Greenland over the past ~100 years, we hypothesized that earlier European interactions, such as pre-colonial Dutch whalers and early German and Danish-Norwegian missionaries, as well as the later Danish colonists and post-colonial immigrants, all contributed European genetic ancestry. However, we found that the European ancestry is almost entirely Danish and that a substantial fraction is from admixture that took place within the last few generations.

Highlights

The genetic analyses suggest that the European ancestry of the present-day Greenlanders is predominantly Danish and the result of very recent gene flow
The lack of genetic ancestry originating from the early exploration activities by the British is perhaps the least surprising, because these activities only involved a few ships
The relatively small amount of ancestry originating from German Moravian missionaries, who stayed in Greenland for about 170 years until 1900, may be explained by the restrictions that the Moravian Brethren put on intermarriage with the Greenlandic population.[19]

Summary

Methods

Greenlandic genotype data All Greenlandic participants were genotyped on two SNP arrays: the CardioMetaboChip (196,224 SNPs)[2,22,32] and the Multi-Ethnic Global Array (1.5M SNPs).[33] Data from these two SNP arrays were merged on the plus strand and 3972 individuals with genotypes from both SNP arrays and a missing rate below 0.02 were retained. From these we removed singletons, sites not on an autosome, as well as sites with a significant (p

Results

Discussion

Conclusion