Population Genetic Diversity and Phylogenetic Characteristics for High-Altitude Adaptive Kham Tibetan Revealed by DNATyperTM 19 Amplification System

Abstract

Tibetans residing in the high-altitude inhospitable environment have undergone significant natural selection of their genetic architecture. Recently, highly mutational autosomal short tandem repeats were widely used not only in the anthropology and population genetics to investigate the genetic structure and relationships, but also in the medical genetics to explore the pathogenesis of multiple genetic diseases and in the forensic science to identify individual and parentage relatedness. However, genetic variants and forensic efficiency of DNATyperTM 19 amplification system and genetic background of Kham Tibetan remain uncharacterized. Thus, we genotyped 19 forensic genetic markers in 11,402 Kham Tibetans to gain insight into the genetic diversity of Chinese high-altitude adaptive population. Highly discriminating and polymorphic forensic measures were observed, which indicated that this new-developed DNATyper 19 PCR amplification is suitable for routine forensic identification purposes and Chinese national DNA database establishment. Pairwise genetic distances among the comprehensive population comparisons suggested that this high-altitude adaptive Kham Tibetan has genetically closer relationships with lowlanders of Tibeto-Burman-speaking populations (Chengdu Tibetan, Liangshan Tibetan, and Liangshan Yi). Genetic substructure analyses via phylogenetic reconstruction, principal component analysis, and multidimensional scaling analysis in both nationwide and worldwide contexts suggested that the genetic proximity exists along the linguistic, ethnic, and continental geographical boundary. Further studies with whole-genome sequencing of modern or archaic Kham Tibetans would be useful in reconstructing the Tibetan population history.

Peopling History of the Tibetan Plateau and Multiple Waves of Admixture of Tibetans Inferred From Both Ancient and Modern Genome-Wide Data

“…Ancient/modern genomes from the TP showed a clear connection with the northern modern Han Chinese and Neolithic-NEAs, especially with the coastal Houli people from Shandong, inland Yangshao and Longshan people from Henan, and Qijia people from Ganqing region, which supported the northern China origin of modern Tibeto-Burman-speaking populations. Shared ancestry revealed by our PCA, pairwise F ST and outgroup-f 3 -values, ADMIXTURE, and f 4 -statistics among ancient/modern highlanders and NEA lowlanders showed their close relationship, which was consistent with genetic similarities revealed by the forensic low-density genetic markers and uniparental haplotype/haplogroup data (Zou et al, 2018;Chen P. et al, 2019;He et al, 2019). Direct evidence supported and confirmed this proposed common origin of the Sino-Tibetan (North China origin hypothesis) that was provided by the phylogenetic relationship reconstruction.…”

“…Contemporary Tibetans could trace their main ancestry back to the Neolithic millet farmers ( Li et al, 2019 ). Moreover, the genetic variations of modern Tibetan groups have also been explored based on the forensically available markers ( Wang Z. et al, 2018 ; Zou et al, 2018 ; He et al, 2019 ). However, the low resolution of these markers hindered the comprehensive understanding of prehistoric human activities on the TP and impeded the dissection of the ancestral component of Tibetans.…”

Combined Low-/High-Density Modern and Ancient Genome-Wide Data Document Genomic Admixture History of High-Altitude East Asians

“…Linguistic study from the Bayesian phylogenetic analysis of the Sino-Tibetan language family has suggested that the Tibeto-Burman-speaking populations diverged from Han Chinese with an average coalescence age of approximately 5.9 kya ( Zhang et al, 2019 ). Furthermore, genetic observations based on forensically related markers also revealed the consistent phylogenetic relationships between Tibetan and other geographically or ethnically different groups ( He et al, 2018a , b ; Wang et al, 2018b , 2020 ; Zou et al, 2018 ; Li et al, 2019a ).…”

Genetic structure and forensic characteristics of Tibeto-Burman-speaking Ü-Tsang and Kham Tibetan Highlanders revealed by 27 Y-chromosomal STRs

“…To gain insights into the genetic diversity and forensic characteristics of forensic Y-chromosomal genetic markers, we genotyped and analyzed 27 Y-STRs in 230 Shigatse Ü-Tsang Tibetans (SUT) and 172 Chamdo Kham Tibetans (CKT). Subsequently, we performed comprehensive population comparisons corresponding to cultural, geographical or linguistic groups to dissect the genetic similarities and differences between our studied Tibetan populations and Chinese reference populations or other adjacent Tibetan-Burman speaking populations 20,35–42 .…”