There was a question about East Asian genetic structure. There have been a fair number of papers published on the issue. But over the years I’ve assembled a pretty large personal data set from public sources, as well as stuff people have sent me. I decided to look at the East Asian individuals and how they relate to each.
First, I focused on the major ethno-national groups (or ones of particular interest and relevance, such as Mongols). Second, I LD pruned the data set down to 96,000. Third, I did some outlier removal. For example, I wanted to include some Kalmyk data, but it turns out all the Kalmyk have European admixture at some level. And a subset of individuals from Cambodia and Vietnam are ethnic Chinese. Those were removed.
I ran ADMIXTURE K = 5 unsupervised. Treemix k = 500 and global rearrangements on, and rooted with Cambodians.
Eigenvalues 7.59041, 4.04862, 3.00559, 2.60692 and 2.01554.
First, the evidence of gene flow into the Han ethnicity, or the absorption of the Han of local substrate, is clear in these results. Second, I’m pretty sure that the weird affinity between Yakut (the northernmost Turks) and Cambodians has to do with admixture into both groups from non-East Eurasians that is old. In the case of Cambodians something Indian-like, and for Yakuts something more like “Ancient North Eurasians.”