Y-chromosome evidence of southern origin of the East Asian-specific haplogroup O3-M122

Abstract

The prehistoric peopling of East Asia by modern humans remains controversial with respect to early population migrations. Here, we present a systematic sampling and genetic screening of an East Asian-specific Y-chromosome haplogroup (O3-M122) in 2,332 individuals from diverse East Asian populations. Our results indicate that the O3-M122 lineage is dominant in East Asian populations, with an average frequency of 44.3%. The microsatellite data show that the O3-M122 haplotypes in southern East Asia are more diverse than those in northern East Asia, suggesting a southern origin of the O3-M122 mutation. It was estimated that the early northward migration of the O3-M122 lineages in East Asia occurred approximately 25,000-30,000 years ago, consistent with the fossil records of modern humans in East Asia.

Figure 1

The phylogenetic relationships of the O3-M122 SNPs and haplotypes

Figure 2

The frequency distribution of the O3-M122 haplotypes in East Asian and other continental populations. The data used were from published studies (Su et al. , , ; Qian et al. ; Semino et al. ; Underhill et al. ; Karafet et al. ; Lell et al. ; Jin et al. ; Wen et al. 2004a).

Figure 3

The geographic distribution of language families/subfamilies in East Asia (Wang 1994) and the sampling sites for the present study. The population labels correspond with those in table 2.

Figure 4

The contour maps of the Y-haplotype–frequency distribution. The data used to construct the contour maps of O3-M122, O3a-M324, O3a5-M134, and O3a4-M7 were from published studies (Su et al. , , ; Qian et al. ; Wen et al. 2004a) and the present study. The data used to construct the contour maps of O3a* and O3a5a2 (M117) were from the present study.

Figure 5

The map of multidimensional scaling analysis based on the O3-M122 SNP haplotype distribution (table 2) of the 40 populations studied. Three dimensions were used in construction of the MDS map.

Figure 6

The networks of Y-STR haplotypes under the background of the Y SNPs. A, Network constructed with use of all populations. Populations shown in blue are northern Han. Populations shown in red are southern populations (Daic, Hmong-Mien, and Austro-Asiatic). Populations shown in green are southern Han and Tibeto-Burmans. B, Network constructed with southern Han, Altaic, Tibeto-Burman, and Hmong-Mien populations excluded to remove the influence of recent population admixture. Blue represents northern Han. Red represents Daic and Austro-Asiatic populations. The sizes of the dots are proportional to the haplotype frequencies, and the dots with multiple colors represent haplotypes shared among populations.