title: Genetic evidence of paleolithic colonization and neolithic expansion of modern humans on the tibetan plateau.
abstract: Tibetans live on the highest plateau in the world, their current population size is approximately 5 million, and most of them live at an altitude exceeding 3,500 m. Therefore, the Tibetan Plateau is a remarkable area for cultural and biological studies of human population history. However, the chronological profile of the Tibetan Plateau's colonization remains an unsolved question of human prehistory. To reconstruct the prehistoric colonization and demographic history of modern humans on the Tibetan Plateau, we systematically sampled 6,109 Tibetan individuals from 41 geographic populations across the entire region of the Tibetan Plateau and analyzed the phylogeographic patterns of both paternal (n = 2,354) and maternal (n = 6,109) lineages as well as genome-wide single nucleotide polymorphism markers (n = 50) in Tibetan populations. We found that there have been two distinct, major prehistoric migrations of modern humans into the Tibetan Plateau. The first migration was marked by ancient Tibetan genetic signatures dated to approximately 30,000 years ago, indicating that the initial peopling of the Tibetan Plateau by modern humans occurred during the Upper Paleolithic rather than Neolithic. We also found evidences for relatively young (only 7-10 thousand years old) shared Y chromosome and mitochondrial DNA haplotypes between Tibetans and Han Chinese, suggesting a second wave of migration during the early Neolithic. Collectively, the genetic data indicate that Tibetans have been adapted to a high altitude environment since initial colonization of the Tibetan Plateau in the early Upper Paleolithic, before the last glacial maximum, followed by a rapid population expansion that coincided with the establishment of farming and yak pastoralism on the Plateau in the early Neolithic.
authors.affiliation: State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.
authors.forename: Xuebin
authors.initials: X
authors.lastname: Qi
authors.forename: Chaoying
authors.initials: C
authors.lastname: Cui
authors.forename: Yi
authors.initials: Y
authors.lastname: Peng
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Zhang
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Yang
authors.forename: Hua
authors.initials: H
authors.lastname: Zhong
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.forename: Kun
authors.initials: K
authors.lastname: Xiang
authors.forename: Xiangyu
authors.initials: X
authors.lastname: Cao
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
authors.lastname: Ouzhuluobu
authors.lastname: Basang
authors.lastname: Ciwangsangbu
authors.lastname: Bianba
authors.lastname: Gonggalanzi
authors.forename: Tianyi
authors.initials: T
authors.lastname: Wu
authors.forename: Hua
authors.initials: H
authors.lastname: Chen
authors.forename: Hong
authors.initials: H
authors.lastname: Shi
authors.forename: Bing
authors.initials: B
authors.lastname: Su
mesh_terms: D044466:Asian People / Q000235:genetics*; D041322:Chromosomes, Human, Y; D004272:DNA, Mitochondrial / Q000235:genetics; D004641:Emigration and Immigration; D019143:Evolution, Molecular; D005260:Female; D014644:Genetic Variation; D005843:Geography; D006239:Haplotypes; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide; D011157:Population Dynamics; D018609:Tibet
chemical_list: D004272:DNA, Mitochondrial
keywords: Tibetan Plateau; demographic history; human migration; last glacial maximum