Genetic and linguistic landscapes of Gansu-Qinghai populations

The Gansu-Qinghai (GQ) region is a critical Eurasian contact zone with exceptional linguistic and genetic diversity. However, genomic studies integrating genetic and linguistic evidence in areas with intensive language mixing remain limited. We conducted fine-scale genomic analyses on 153 new samples from four linguistically mixing or mixed regions: Linxia and Xiahe in Gansu, and Gan'gou and Wutun in Qinghai. Our findings reveal three primary ancestral components: Yellow River, western Eurasian steppe, and Tibetan Plateau (TP)-related lineages. While non-Han populations show pronounced genetic heterogeneity and varying patterns of language maintenance, Han populations exhibit asymmetric convergence. Specifically, the Wutun Han show concordant genetic and linguistic shifts, whereas other Han groups exhibit linguistic structural convergence without corresponding gene flow. Widespread east-west admixture was detected in both Han Chinese and non-Han populations from the GQ region, primarily dating to the Tang/Song and Yuan Dynasties. Together, our interdisciplinary genetic-linguistic framework reveals complex and asymmetric processes underlying population interaction and language evolution in the GQ contact zone.