http://bmcgenet.biomedcentral.com/articles/10.1186/s12863-015-0237-5
QuoteOur results indicate that the people of the Tarim Basin had a diverse maternal ancestry, with origins in Europe, central/eastern Siberia and southern/western Asia. These findings, together with information on the cultural context of the Xiaohe cemetery, can be used to test contrasting hypotheses of route of settlement into the Tarim Basin.
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Our data indicate multiple population influences in the Tarim Basin during 4000–3500 yBP, consistent mainly with the "steppe hypothesis", but with elements of the "oasis hypothesis". Meanwhile, we can't exclude the possibility that East Asians had an indirect impact on the Tarim Basin at Bronze Age.