As reported in the New York Times, the cover article of Nature this week describes the sequencing of a Paleo-Eskimo genome from Greenland. This is the first ancient sequence from the New World, and is important for a number of reasons:
- The sequence analysis was conducted from a sample of human hair that was recovered from permafrost, and the DNA was recovered from the hair shaft, not the root. This opens a whole new avenue of paleogenomic research.
- SNP analysis shows that the hair belonged to an individual who carried a number of traits frequently found in modern Asian populations, including shovel-shaped incisors and dry ear wax.
- 85-87% of the genome was sequenced – phenomenal coverage given the age of the sample.
Chukchi women (seated front right), circa 1906
- Population genetic analysis (principle component analysis of genetic distances) revealed the closest relationship between the Greenland genome and the Chukchi, a population in northern Siberia, suggesting a recent migration (in the last ~5,000 years) from Siberia across the Arctic to Greenland. This would be in addition to the three migrations (Amerind, Na-Dene, and Eskimo-Aleut) traditionally hypothesized for the peopling of the New World.
Rasmussen et al. (2010) Figure 3b. PCA of populations - Saqqaq genome indicated by star.
I was disappointed that more North American samples weren’t included in the analysis. With the exception of populations from West and East Greenland, Na-Dene in western Canada, and Aleuts, the only other Native American groups are from Central and South America. But overall, this study demonstrates how ancient DNA analysis can help answer historical questions.
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Disclaimer: One of the co-authors (Michael Crawford) was my graduate mentor. Which, for me, makes this study even more awesome.
Image credit: Wikimedia Commons
Rasmussen, M., Li, Y., Lindgreen, S., Pedersen, J., Albrechtsen, A., Moltke, I., Metspalu, M., Metspalu, E., Kivisild, T., Gupta, R., Bertalan, M., Nielsen, K., Gilbert, M., Wang, Y., Raghavan, M., Campos, P., Kamp, H., Wilson, A., Gledhill, A., Tridico, S., Bunce, M., Lorenzen, E., Binladen, J., Guo, X., Zhao, J., Zhang, X., Zhang, H., Li, Z., Chen, M., Orlando, L., Kristiansen, K., Bak, M., Tommerup, N., Bendixen, C., Pierre, T., Grønnow, B., Meldgaard, M., Andreasen, C., Fedorova, S., Osipova, L., Higham, T., Ramsey, C., Hansen, T., Nielsen, F., Crawford, M., Brunak, S., Sicheritz-Pontén, T., Villems, R., Nielsen, R., Krogh, A., Wang, J., & Willerslev, E. (2010). Ancient human genome sequence of an extinct Palaeo-Eskimo Nature, 463 (7282), 757-762 DOI: 10.1038/nature08835
