Long term genetic stability and a high altitude East Asian origin for the peoples of the high valleys of the Himalayan arc
Significance Since prehistory, the Himalayan mountain range has presented a formidable barrier to population migration, whereas at the same time its transverse valleys have long served as conduits for trade and exchange. Yet, despite the economic and cultural importance of Himalayan trade routes, little is known about the region's peopling and early population history. In this study, we conduct to our knowledge the first ancient DNA investigation of the Himalayan arc and generate genome data for eight individuals ranging in time from the earliest known human settlements to the establishment of the Tibetan Empire. We demonstrate that the region was colonized by East Asians of likely high altitude origin, followed by millennia of genetic continuity despite marked changes in material culture and mortuary behavior. The high altitude transverse valleys >3,000 m above sea level (masl) of the Himalayan arc from Arunachal Pradesh to Ladahk were among the last habitable places permanently colonized by prehistoric humans due to the challenges of resource scarcity, cold stress, and hypoxia. The modern populations of these valleys, who share cultural and linguistic affinities with peoples found today on the Tibetan plateau, are commonly assumed to be the descendants of the earliest inhabitants of the Himalayan arc. However, this assumption has been challenged by archaeological and osteological evidence suggesting that these valleys may have been originally populated from areas other than the Tibetan plateau, including those at low elevation. To investigate the peopling and early population history of this dynamic high altitude contact zone, we sequenced the genomes (0.04x 7.25x, mean 2.16x) and mitochondrial genomes (20.8x 1,311.0x, mean 482.1x) of eight individuals dating to three periods with distinct material culture in the Annapurna Conservation Area (ACA) of Nepal, spanning 3,150 1,250 y before present (yBP) We demonstrate that the region is characterized by long term stability of the population genetic make up despite marked changes in material culture. The ancient genomes, uniparental haplotypes, and high altitude adaptive alleles suggest a high altitude East Asian origin for prehistoric Himalayan populations.
Proceedings of the National Academy of Sciences