Investigating the paternal genetic structure and migration history of Chinese Qiang minority by Y-chromosome short tandem repeats.

Known for its legendary history and peculiar culture, Chinese Qiang minority aroused interest among geneticists and anthropologists. However, the paternal genetic landscape of its sub-branches coupled with its migration history has never been uncovered. In this study, 37 Y-chromosomal short tandem repeat (Y-STR) loci of three Qiang ethnic groups (N = 564) were investigated to shed light on their paternal genetic landscape. The phylogenetic reconstruction among 29 populations was conducted based on their Y-chromosomal haplotypes. The genetic affinities of the four different Qiang subgroups exhibited obviously variant when compared with Han, Yi or Tibetan in Tibetan-Yi corridor. Based on machine learning method, the predicted Y chromosome haplogroups demonstrated the predominance of O2a1 and O2a2. The haplogroup distributions were compared among 40 contemporary ethnic groups in West China and DNA samples of 214 ancient humans from 59 archaeological sites. The results supported that Wenchuan Qiang had historical links with the ancients in West Liao River (WLR) region. Moreover, intrapopulation gene flow was analysed using Migrate-n. Bidirectional migration was proved to be the most frequent model among the Qiangic populations while the unidirectional migration was only observed from Wenchuan to Li County.