 The occurrence of the Subhaplogroups D1a and C1a in the lower Amur region suggests a source population from that region distinct from the Altai-Baikal source populations, where sampling did not reveal those two particular subclades.The conclusions regarding Subhaplogroup D1 indicating potential source populations in the lower Amur and Hokkaido areas stand in contrast to the single-source migration model.Subhaplogroup D4h3 has been identified among Han Chinese.