Genetic characteristics ofApodemus speciosusat Akiyoshidai Quasi-National Park in Yamaguchi Prefecture

abstract The large Japanese field mouse ( Apodemus speciosus ) is a small rodent endemic to Japan. The mice have a genetic characteristic in which the number of chromosomes differs between those from western Japan and those from eastern Japan. A. spesiosus , found throughout Japan, is used as a model animal for geogenetics and monitoring of radiation effects of wildlife. In this present study, to elucidate the genetic characteristics of the mice Akiyoshidai Quasi-National Park in Yamaguchi Prefecture, we investigated mitochondrial DNA and chromosome numbers. As a result, A. speciosus from Yamaguchi Prefecture were classified into the Honshu-Shikoku-Kyushu group and had a western Japan-type chromosome set of 2n=46; however, some Yamaguchi Prefecture mice formed a genetic cluster in Yamaguchi Prefecture, suggesting that continuous monitoring is needed to reveal the dynamics of genetic diversity.