Genetic Origins and Sex-Biased Admixture of the Huis

The Hui people are unique among Chinese ethnic minorities in that they speak the same language as Han Chinese (HAN) but practice Islam. However, as the second-largest minority group in China numbering well over 10 million, the Huis are under-represented in both global and regional genomic studies. Here, we present the first whole-genome sequencing effort of 234 Hui individuals (NXH) aged over 60 who have been living in Ningxia, where the Huis are mostly concentrated. NXH are genetically more similar to East Asian than to any other global populations. In particular, the genetic differentiation between NXH and HAN (F-ST = 0.0015) is only slightly larger than that between northern and southern HAN (F-ST = 0.0010), largely attributed to the western ancestry in NXH (similar to 10%). Highly differentiated functional variants between NXH and HAN were identified in genes associated with skin pigmentation (e.g., SLC24A5), facial morphology (e.g., EDAR), and lipid metabolism (e.g., ABCG8). The Huis are also distinct from other Muslim groups such as the Uyghurs (FST = 0.0187), especially, NXH derived much less western ancestry (-10%) compared with the Uyghurs (similar to 50%). Modeling admixture history indicated that NXH experienced an episode of two-wave admixture. An ancient admixture occurred 1,025 years ago, reflecting the intensive west-east contacts during the late Tang Dynasty, and the Five Dynasties and Ten Kingdoms period. A recent admixture occurred similar to 500 years ago, corresponding to the Ming Dynasty. Notably, we identified considerable sex-biased admixture, that is, excess of western males and eastern females contributing to the NXH gene pool. The origins and the genomic diversity of the Hui people imply the complex history of contacts between western and eastern Eurasians.

Automated summary

The Hui people, a unique ethnic minority in China who speak Mandarin and practice Islam, showed genetic similarity to East Asian populations and significant functional genetic variations in skin pigmentation, facial morphology, and lipid metabolism. Their history includes two episodes of admixture, reflecting interactions between western and eastern Eurasians during different periods. Strong sex-biased admixture was also observed, with an excess of western males and eastern females contributing to the genetic pool of the Hui people.