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bioRxiv · 10.1101/2023.06.16.545243

Distinguished biological adaptation architecture aggravated population differentiation of Tibeto-Burman-speaking people inferred from 500 whole genome data from 39 populations

Abstract

Tibeto-Burman (TB) people have tried to adapt to the hypoxic, cold and high-UV high-altitude Tibetan Plateau and complex disease exposure in the lowland wet and hot rainforest since the late Paleolithic period. However, the full landscape of genetic history and biological adaptation of geographically diverse TB people and their interaction mechanism remained unknown. We generated a whole-genome-based meta-database of 500 individuals from 39 TB populations from East Asia and Southeast Asia and presented a comprehensive landscape of genetic diversity, admixture history and differentiated adaptative features of geographically different TB people. We identified geography/language-related genetic differentiation among Tibetan Plateau, Tibetan-Yi-Corridor (TYC) and Southeast Asian TB people, consistent with their differentiated admixture process with incoming or indigenous ancestral source populations. A robust genetic connection between TYC people and ancient YR people supported the Northern origin hypothesis of TB people. We reported population substructure-related differentiated biological adaptative signatures between highland Tibetans and lowland TB people and between geographically different Lolo speakers. Highland adaptative EPAS1 and EGLN variants riched in Tibetans but lacked in TYC people whose adaptation is associated with the physical features and skin pigmentation (EDAR and SLC24A5), hepatic alcohol metabolism (ALDH9A1), regulation of cell-cell adhesion of muscle cells (CTNNA3) and immune/fat metabolism-related adaptative signature. TB-related genomic resources provided new insights into the genetic basis of phenotype differences and better reference for the anthropologically-informed sampling design in biomedical and genomic cohort research.

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BibTeXRIS

Sun, Y., Wang, M., Sun, Q., Liu, Y., Duan, S., Wang, Z., Zhou, Y., Zhong, J., Huang, Y., Huang, X., Li, X., Su, H., Cai, Y., Jiang, X., Chen, J., Yan, J., Nie, S., Hu, L., Yang, J., Tang, R., Wang, C.-C., Liu, C., Deng, X., He, G., Yun, L.. 2023-06-21. Distinguished biological adaptation architecture aggravated population differentiation of Tibeto-Burman-speaking people inferred from 500 whole genome data from 39 populations. https://doi.org/10.1101/2023.06.16.545243

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