Thursday, November 8, 2012

Major new Ainu genetic study forthcoming

Major new Ainu genetic study forthcoming:



Genetic kinship found between Ainu and native Okinawans (The Asahi Shimbun):


The researchers examined and compared the DNA of 36 Ainu, 35 native Okinawans, and 243 people living in Honshu and elsewhere in Japan. They also studied the DNA of ethnic Han Chinese living in Beijing. The Ainu DNA was from stored samples that had been collected about 30 years ago.



The analysis found that the DNA of the Ainu bore closest similarity to people who had lived for generations in Okinawa. There was increasing dissimilarity with--in this order--those from Honshu, South Koreans and Chinese.


Meanwhile, the researchers found that the DNA of people living in Honshu showed similarities with that of South Koreans and Chinese.



The findings were to be published Nov. 1 in the Journal of Human Genetics.

I don't see the paper on the journal site yet. Loh et al. (2012) were able to infer that admixture in the Japanese occurred 45 +/- 6 generations ago, and involved at least 41 +/- 3% Yayoi ancestry. Another recent paper (He et al. 2012) estimated 23.1∼39.5% "Paleolithic" ancestry in mainland Japanese. But both studies lacked an Ainu genetic sample, which will apparently now become available (and I hope publicly so).



It will now be possible both to do a 2-reference text of admixture with software like ALDER for the Japanese, but also, and perhaps more importantly, to do a 1-ref test of admixture for the Ainu themselves! It is important to remember that the Ainu are not unmodified descendants of the Jomon, and their own ancestry is likely to be complex.



And, there will now be a second population of Y-haplogroup D descendants (the Ainu) to complement the Andamanese islanders genotyped by Reich et al. (2009). It is not clear to me whether there will be any autosomal signal left to link these peoples together, but the issue can now be investigated.



Finally, there is the whole issue of the relationship of the Ainu with West Eurasians; while research has not been supportive of that notion, it may still be useful to see whether the hirsuteness of the Ainu and other phenotypic similarities with Europeans have the same genetic aetiology or not. A link of a different kind that might be useful to investigate is the East Eurasian/Amerindian-like gene flow into Europe which seems to be more pronounced for Amerindians: will the signal also be present for the Ainu, and how strong will it be? And, of course there is that whole other issue of levels of affinity to Eurasian archaic hominins...



It is great that the last few gaps in our sampling of world genetic variation are being filled. Time and again we have discovered that at the "edges of variation" we often find the most interesting nuggets of information about our prehistoric past (e.g., Sardinians re: prehistoric Europe, Australo-Melanesians re: Denisovan admixture, Amerindians re: North Eurasian admixture in Europe, Khoe-San re: earliest divergences in the human family). The Ainu are likely to offer us new insight not only about their own origins, and those of the Japanese, but also about events taking place much further from the isles of Japan.





DIGITAL JUICE

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