Differences in c-band patterns between the Japanese house mice (Mus musculus) in Hokkaido and Eastern Honshu

We characterized and categorized the C-band patterns of the house mouse Mus musculus from four areas in Hokkaido and Honshu of the Japanese Islands as a biparental marker. The C-band patterns are categorized as polymorphic, monomorphic, or intermediate, corresponding to those of the Korean mice, C57BL/6, and F1 hybrid mice bred from the Japanese mice and a laboratory mouse, respectively. The C-band patterns mainly differ between mice from Hokkaido and Honshu. The polymorphic patterns are shown in mice in Honshu, while the intermediate patterns are shown in mice in Hokkaido, with an exceptional case of a monomorphic pattern found in one locality. In the other localities of Hokkaido and northeastern Honshu, the C-band patterns are not congruent with an estimation by maternal element in our previous study, whereas the congruence is observed in other localities. It is suggested that the characteristics of the Japanese house mice have been formed through complicated processes by different expansions between biparental and maternal elements.