Phylogenomic Analyses Revealed a New Lineage of House Mouse (Mus Musculus) in Gyirong Basin of Xizang Autonomous Region, China

Abstract

In present study, we collected 20 individuals and 12 individuals of wild mice from Gyirong Basin of Xizang Autonomous Region in China and Sudurpashchim of Nepal, respectively. Phylogeny and genetic structure inferred from different types of genomic marker suggest that these samples all belong to Mus musculus, among which individuals from Gyirong Basin represent a new genomic lineage (named as M. m. gyirongus), and samples from Sudurpashchim represent intermediate population between central population and M. m. castaneus. M. m. gyirongus, along with M. m. domesticus and M. m. musculus, differentiated from central population compactly during ~267,000 to 227,000 years ago in interglacial period. Three lineages all experienced continuous population decline before ~70,000 years ago. Then, they underwent population fluctuations at different time periods that might impacted by climate changes, migration history and human activities. Genes related to regulation of cell cycle and carcinogenesis, structure and function of neural synapses, reproduction and embryonic development, and immune response induced by pathogen infection had undergone positive selection in genome of M. m. gyirongus. The discovery of M. m. gyirongus not only can help us to better understand the evolutionary history of M. musculus, but also can provide new regional resources for breeding novel laboratory mouse strains.

Keywords: House mice, New lineage， Gyirong Basin， Phylogenomic，Morphology