Maanasa Raghavan and colleagues published the complete sequence of the oldest (thus far) modern human genome in Nature today (“Upper Palaeolithic Siberian genome reveals dual ancestry of Native Americans”).
This genome is important not only because it’s so old (dating to about 24,000 years before present), but also because it’s from the Lake Baikal region in Siberia, which is where the population ancestral to Native Americans has long been thought to have come from. Analysis of the genome shows that it is indeed closely related to Native American populations, which supports the hypothesis of their Siberian ancestry.
Interestingly, the ancient Siberian genome also shows close affinity with modern Western Eurasian populations. What does this mean? The New York Times report on this article suggests a number of scenarios, but I am a bit more cautious about inferring too much about population history from one genome as I explain in this LiveScience article.
The results from this cool study show that the genetic landscape of Siberia has changed quite a bit over the last 24,000 years. It’s yet another reminder that our conceptions of what is “European” or “Asian” genetically is based on modern patterns of diversity. Taken to its extremes, this can be a bit essentialist, as population movement and random genetic changes over time have certainly brought about changes to the geographic distributions of lineages.
I can’t emphasize enough how technically difficult it is to sequence even the tiniest portions of ancient DNA, let alone complete genomes, let alone complete genomes this old. This paper is a fantastic achievement, and I hope that we will see more ancient genomes from this region in the near future.
UPDATE: I’m also quoted in a Nature article discussing this paper–check it out!