| 描述信息 |
As many human populations settled at Central Asia, Kazakh people demonstrate an array of mixed anthropological features of east Eurasian (EEA) and west Eurasian (WEA), indicating a possible scenario of biological admixture between already differentiated EEA and WEA populations. However, their complex biological origin and genomic make-up, as well as their genetic interaction with surrounding populations are not well understood. In an attempt to decipher their genetic structure and population history, we conducted, to our knowledge, the first whole-genome sequencing study of the Kazakhs residing in Xinjiang (KZK). We demonstrated that the KZK derived their ancestries from the four ancestral source populations, i.e., East Asian (~39.7%), West Asian (~28.6%), Siberian (~23.6%), and South Asian (~8.1%). The recognizable interactions of EEA and WEA ancestries in Kazakhs could be dated back to the time period AD 920 - 1036, roughly corresponding to the Five Dynasties and Ten Kingdoms period and early Song Dynasty. The Kazakhs are genetically distinctive from Uyghurs in terms of their overall genomic make-up, although the two populations are closely-related in genetics and both showed substantial admixture of EEA and WEA ancestries. Notably, we identified considerable sex-biased admixture, i.e., excess of western males and eastern females contributing to the KZK gene pool. We further identified a set of genes showing remarkable differentiation in KZK from surrounding populations, such as those are associated with skin color (SLC24A5, OCA2), essential hypertension (HLA-DQB1), hypertension (MTHFR, SLC35F3), neuron development (CNTNAP2). These results advanced our understanding of the complex history of contacts between western and eastern Eurasians especially that along the old Silk Road. |
