Ancient genome analyses shed light on the origin and kinship among humans of a cliff tomb from southwestern China

Abstract

The cliff tomb was a distinctive regional burial form that lasted for centuries in the southwestern region of China. However, the origin of cliff tombs and the genetic relatedness among the co-buried individuals remain elusive. Here, we successfully identified four individuals from the scatted bone fragments in a single cliff tomb in the Sichuan Basin by using ancient DNA and physical anthropology analyses, and retrieved genomic data for the four individuals, to our best knowledge, the first ancient genomic data from the region. Our findings provide direct evidence supporting the Central Plains of China hypothesis for the people who practiced cliff tombs and further suggest that cliff tombs burial practices may also originate from the Central Plains of China, as supported by ancient DNA, archaeological and historical attestations. We successfully reconstructed the family tree of the four individuals and provided concrete evidence that individuals buried in the same cliff tomb are from a nuclear family rather than the long-hypothesized extended family, suggesting that genetic kinship plays a significant role for burial customs in the Sichuan Basin.