Genetic substructure and admixture of Mongolians and Kazakhs inferred from genome-wide array genotyping

Abstract

Background

Mongolian populations are widely distributed geographically, showing abundant ethnic diversity with geographic and tribal differences.

Aim

To infer the genetic substructure, admixture and ancient genetic sources of Mongolians together with Kazakhs

Subjects and methods

We genotyped more than 690,000 genome-wide SNPs from 33 Mongolian and Chinese Kazakh individuals and compared these with both ancient and present-day Eurasian populations using Principal Component Analysis (PCA), ADMIXTURE, Refine-IBD, f statistics, qpWave and qpAdm.

Results

We found genetic substructures within Mongolians corresponding to Ölöd, Chahar, and Inner Mongolian clusters, which was consistent with tribe classifications. Mongolian and Kazakh groups derived about 6–40% of West Eurasian related ancestry, most likely from Bronze Age Steppe populations. The East Asian related ancestry in Mongolian and Kazakh groups was well represented by the Neolithic DevilsCave related nomadic lineage, comprising 42–64% of studied groups. We also detected 10–51% of Han Chinese related ancestry in Mongolian and Kazakh groups, especially in Inner Mongolians. The average admixture times for Inner Mongolian, Mongolian_Chahar, Mongolian_Ölöd and Chinese Kazakh were about 1381, 626, 635 and 632 years ago, respectively, with Han and French as the sources.

Conclusion

The DevilsCave related ancestry was once widespread westwards covering a wide geographical range from Far East Russia to the Mongolia Plateau. The formation of present-day Mongolic and Turkic-speaking populations has also received genetic influence from agricultural expansion.

Keywords:

• Population genetics
• genetic admixture
• population structure

Acknowledgements

The authors thank Tu Penske, a cadre of Ulanbrook Village, Nilka County in Xinjiang, for assisting in the collection of samples.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was funded by National Natural Science Foundation of China [NSFC 31801040, 61372151], Nanqiang Outstanding Young Talents Program of Xiamen University [X2123302], and Fundamental Research Funds for the Central Universities [ZK1144].