Tuesday, June 23, 2015

More Ancient DNA!

Via Eurogenes (emphasis added):
The Y-chromosome belongs to macrohaplogroup F and the mtDNA to macrohaplogroup N. For details see the supp info PDF here. The full paper is freely available here.

Qiaomei Fu et al., An early modern human from Romania with a recent Neanderthal ancestorNature(2015) doi:10.1038/nature14558
Abstract: Neanderthals are thought to have disappeared in Europe approximately 39,000–41,000 years ago but they have contributed 1–3% of the DNA of present-day people in Eurasia. Here we analyse DNA from a 37,000–42,000-year-old modern human from Peştera cu Oase, Romania. Although the specimen contains small amounts of human DNA, we use an enrichment strategy to isolate sites that are informative about its relationship to Neanderthals and present-day humans. We find that on the order of 6–9% of the genome of the Oase individual is derived from Neanderthals, more than any other modern human sequenced to date. Three chromosomal segments of Neanderthal ancestry are over 50 centimorgans in size, indicating that this individual had a Neanderthal ancestor as recently as four to six generations back. However, the Oase individual does not share more alleles with later Europeans than with East Asians, suggesting that the Oase population did not contribute substantially to later humans in Europe.
The ability of science to present this evidence is absolutely stunning.  The lack of a West Eurasian v. East Eurasian genetic leaning more than 10,000 years into the Upper Paleolithic, despite lacking any private East Eurasian Y-DNA or mtDNA haplogroups, is surprising.  This also brings to mind the fact that none of the Y-DNA samples of European hunter-gatherers has Y-DNA D or E.

Also via Eurogenes, is the paper below, which analyzes a limited reconstruction of a Neolithic individual from what is today Barcin, Turkey:
Pinhasi R, Fernandes D, Sirak K, Novak M, Connell S, Alpaslan-Roodenberg S, et al. (2015) Optimal Ancient DNA Yields from the Inner Ear Part of the Human Petrous Bone. PLoS ONE 10(6): e0129102. doi:10.1371/journal.pone.0129102
A PCA analysis places the sample near Sardinians, but shifted in the direction of Near Easterners.  Another analysis shows Sardinians, Italian Tuscans, Basque, Turkish Jews, and Western Ukrainians all fairly close.  An ancestral component analysis concludes that:
The lack of Ancient North Eurasian (ANE) ancestry isn't surprising, because it mirrors the results of early European farmers we've seen to date.  
Moreover, the relatively high level of Western European Hunter-Gatherer (WHG) ancestry, or at least something very similar, is also in line with expectations, considering that the sample was dug up in far western Anatolia, almost on the European border. 
Bottom line: Neolithic Western Anatolians look a lot like other first wave Neolithic farmers, confirming the leading paradigm of demic migration in the first wave of the European Neolithic.

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