The Genomic Formation of South and Central Asia

Republication from biorxiv

 

doi: https://doi.org/10.1101/292581 

Abstract

The genetic formation of Central and South Asian populations has been unclear because of an absence of ancient DNA. To address this gap, we generated genome-wide data from 362 ancient individuals, including the first from eastern Iran, Turan (Uzbekistan, Turkmenistan, and Tajikistan), Bronze Age Kazakhstan, and South Asia. Our data reveal a complex set of genetic sources that ultimately combined to form the ancestry of South Asians today. We document a southward spread of genetic ancestry from the Eurasian Steppe, correlating with the archaeologically known expansion of pastoralist sites from the Steppe to Turan in the Middle Bronze Age (2300-1500 BCE). These Steppe communities mixed genetically with peoples of the Bactria Margiana Archaeological Complex (BMAC) whom they encountered in Turan (primarily descendants of earlier agriculturalists of Iran), but there is no evidence that the main BMAC population contributed genetically to later South Asians. Instead, Steppe communities integrated farther south throughout the 2nd millennium BCE, and we show that they mixed with a more southern population that we document at multiple sites as outlier individuals exhibiting a distinctive mixture of ancestry related to Iranian agriculturalists and South Asian hunter-gathers.

Genetic data reveal contrasting sex bias in Neolithic and Bronze Age Eurasian migrations

Republication from PNAS

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Amy Goldberg, Torsten Günther, Noah A. Rosenberg, and Mattias Jakobsson

PNAS March 7, 2017 114 (10) 2657-2662; published ahead of print February 21, 2017

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Significance

Studies of differing female and male demographic histories on the basis of ancient genomes can provide insight into the social structures and cultural interactions during major events in human prehistory. We consider the sex-specific demography of two of the largest migrations in recent European prehistory. Using genome-wide ancient genetic data from multiple Eurasian populations spanning the last 10,000 years, we find no evidence of sex-biased migrations from Anatolia, despite the shift to patrilocality associated with the spread of farming. In contrast, we infer a massive male-biased migration from the steppe during the late Neolithic and Bronze Age. The contrasting patterns of sex-specific migration during these two migrations suggest that different sociocultural processes drove the two events.

Abstract

Dramatic events in human prehistory, such as the spread of agriculture to Europe from Anatolia and the late Neolithic/Bronze Age migration from the Pontic-Caspian Steppe, can be investigated using patterns of genetic variation among the people who lived in those times. In particular, studies of differing female and male demographic histories on the basis of ancient genomes can provide information about complexities of social structures and cultural interactions in prehistoric populations.