Genealogical characterization of regional populations and dorsal coat color variation in the house mouse Mus musculus from Asia based on haplotype structure analysis of a gene-rich region harboring Mc1r

Genes Genet Syst. 2023 Aug 8. doi: 10.1266/ggs.22-00157. Online ahead of print.ABSTRACTWe analyzed 196 haplotype sequences from a gene-rich region (250 kb) that includes Mc1r, a gene involved in coat color regulation, to gain insight into the evolution of coat color variation in subspecies of the house mouse Mus musculus. Phylogenetic networks revealed haplotype groups from the major subspecies of M. m. castaneus (CAS), M. m. domesticus (DOM), and M. m. musculus (MUS). Using haplotype sequences assigned to each of CAS and MUS through phylogenetic analysis, we proposed migration routes associated with prehistoric humans from west to east across Eurasia. Comparing nucleotide diversity among subspecies-specific haplotypes in different geographic areas showed a marked reduction during migration, particularly in MUS-derived haplotypes from Korea and Japan, suggesting intensive population bottlenecks during migration. We found that a C>T polymorphism at site 302 (c.302C>T) in the Mc1r coding region correlated with a darkening of dorsal fur color in both CAS and MUS. However, C/C homozygous mice in MUS showed marked variation in lightness, indicating the possibility of another genetic determinant that affects the lightness of dorsal fur color. Detailed sequence comparisons of haplotypes revealed that short fragments assigned to DOM were embedded in CAS-assigned fragments, indicating ancient introgression between subspecies. The estimated age of c.302C>T also supports the hy...

Source: Genes and Genetic Systems - August 9, 2023 Category: Genetics & Stem Cells Authors: Kazuhiro Zakoh Kazumichi Fujiwara Toyoyuki Takada Naoki Osada Hitoshi Suzuki Source Type: research