How Chinese relate to each other and the Japanese
Last month I pointed to a paper on Chinese population structure, Genomic Dissection of Population Substructure of Han Chinese and Its Implication in Association Studies. One to note was that the average FST differentiation Han populations was on the order of 0.002, while those differentiating Europeans was on the order of 0.009. Below are the various Han population, along with Japanese. CHB = Beijing, while CHD = Denver. The Denver sample is probably biased toward Cantonese and Fujianese, since most American Chinese are from these two groups. As a point of reference, here are South Asian genetic distances.
Interesting. From my understanding it would appear that the Chinese and Japanese are as similarly related as relatively distinct European populations like the Finns and Swedes (whom despite being near physically indistinguishable are not so genetically). The Chinese themselves are near the same order of magnitude of closely related European peoples such as the Germans and the English but slightly more so. The Fst values for various Indian populations though seem to be quite distinctive with even relatively close Fst values being on the same scale as the variance between the Japanese and the Chinese. I do not see how such distinct population clusters were able to form in such close geographic proximity.