River Valleys Shaped the Maternal Genetic Landscape of Han Chinese.

A general south-north genetic divergence has been observed among Han Chinese in previous studies. However, these studies, especially those on mitochondrial DNA (mtDNA), are based either on partial mtDNA sequences or on limited samples. Given that Han Chinese comprise the world's largest population and reside around the whole China, whether the north-south divergence can be observed after all regional populations are considered remains unknown. Moreover, factors involved in shaping the genetic landscape of Han Chinese need further investigation. In this study, we dissected the matrilineal landscape of Han Chinese by studying 4,004 mtDNA haplogroup-defining variants in 21,668 Han samples from virtually all provinces in China. Our results confirmed the genetic divergence between southern and northern Han populations. However, we found a significant genetic divergence among populations from the three main river systems, that is, the Yangtze, the Yellow, and the Zhujiang (Pearl) rivers, which largely attributed to the prevalent distribution of haplogroups D4, B4, and M7 in these river valleys. Further analyses based on 4,986 mitogenomes, including 218 newly generated sequences, indicated that this divergence was already established during the early Holocene and may have resulted from population expansion facilitated by ancient agricultures along these rivers. These results imply that the maternal gene pools of the contemporary Han populations have retained the genetic imprint of early Neolithic farmers from different river basins, or that river valleys represented relative migration barriers that facilitated genetic differentiation, thus highlighting the importance of the three ancient agricultures in shaping the genetic landscape of the Han Chinese.

Inferring the history of surname Ye based on Y chromosome high-resolution genotyping and sequencing data.

Paternal inheritance of both Y chromosome and surnames makes it possible to trace the origin and migration histories of surnames based on high-resolution Y chromosome phylogeny. In this study, 292 male samples with surname Ye () in China were collected to unravel the history of this surname. Among these samples, O-F492 showed the highest frequency (26.71%). Analysis based on Y chromosome genotyping data of 52,798 males from virtually the whole China revealed a close correlation between O-F492 and surname Ye. High-throughput sequencing of 131 unrelated male individuals covering all sub-haplogroups in O-F492 was conducted to update the phylogeny of O-F492. Most of the Ye individuals (43/64, 67.19%) are embedded in three major branches, i.e., O-MF1461, O-MF15219, and O-FGC66159, deriving from the same node (O-FGC66168). These three clades restrictively distributed in different regions, likely attributed to independent differentiations. Coalescent ages of the three subclades are estimated ranging from 1,925 to 1,775 years ago, probably driven by the massive migration from north to south China after Yongjia riot in Jin Dynasty, consistent with the migration history of surname Ye. Our study thus shed important light on the history of the surname Ye from genetic perspective.