Genetic structure of Tibetan populations in Gansu revealed by forensic STR loci

Abstract

The origin and diversification of Sino-Tibetan speaking populations have been long-standing hot debates. However, the limited genetic information of Tibetan populations keeps this topic far from clear. In the present study, we genotyped 15 forensic autosomal short tandem repeats (STRs) from 803 unrelated Tibetan individuals from Gansu Province (635 from Gannan and 168 from Tianzhu) in northwest China. We combined these data with published dataset to infer a detailed population affinities and genetic substructure of Sino-Tibetan populations. Our results revealed Tibetan populations in Gannan and Tianzhu are genetically very similar with Tibetans from other regions. The Tibetans in Tianzhu have received more genetic influence from surrounding lowland populations. The genetic structure of Sino-Tibetan populations was strongly correlated with linguistic affiliations. Although the among-population variances are relatively small, the genetic components for Tibetan, Lolo-Burmese, and Han Chinese were quite distinctive, especially for the Deng, Nu, and Derung of Lolo-Burmese. Han Chinese but not Tibetans are suggested to share substantial genetic component with southern natives, such as Tai-Kadai and Hmong-Mien speaking populations, and with other lowland East Asian populations, which implies there might be extensive gene flow between those lowland groups and Han Chinese after Han Chinese were separated from Tibetans. The dataset generated in present study is also valuable for forensic identification and paternity tests in China.

Cultural variation impacts paternal and maternal genetic lineages of the Hmong-Mien and Sino-Tibetan groups from Thailand

“…Although an MSY lineage (O-M122*) was proposed to be characteristic of all modern ST populations [ 43 ], subsequent studies have found further differentiation, e.g., haplogroup O2a1c-002611, which is at high frequency in Han Chinese but found at very low frequencies in Tibeto-Burman populations [ 44 , 45 ]. Also, autosomal STR genotypes differentiate Tibetan and Lolo-Burmese speaking groups [ 46 ].…”

Genetic polymorphism and phylogenetic differentiation of the Huaxia Platinum System in three Chinese minority ethnicities

“…To illustrate the genetic structure of our three studied populations, a STRUCTURE plot was implemented based on the genotype data of 23 STRs by combining eight previously published populations 7,13–15 . The probable admixture levels and cluster membership patterns of each population are presented in Fig.…”

“…Tibetan belongs to the subbranch of the Tibeto-Burman of the Sino-Tibetan language, which is classified into Sinitic and Tibeto-Burman 12 . A previous study suggested that there are relatively small genetic diversities among Sino-Tibetan populations 13 . The Uygur minority is the fifth largest ethnic group in China and chiefly inhabits the Xinjiang Uygur Autonomous Region of Northwest China.…”

Cultural variation impacts paternal and maternal genetic lineages of the Hmong-Mien and Sino-Tibetan groups from Thailand

“…Although an MSY lineage (O-M122*) was proposed to be characteristic of all modern ST populations (Su et al, 2000), subsequent studies have found further differentiation, e.g. haplogroup O2a1c-002611, which is at high frequency in Han Chinese but found at very low frequencies in Tibeto-Burman populations (Wang et al, 2013, 2014; Yan et al, 2011, 2014; Yao et al, 2017). Also, autosomal STR genotypes differentiate Tibetan and Lolo-Burmese speaking groups (Li et al, 2015; Yao et al, 2017).…”