Genetic diversity and genetic structure of the striped field mouse Apodemus agrarius coreae (Muridae, Rodentia) in Korea

• Apodemus agrarius coreae is characterized by high levels of genetic diversity.
• Korean haplotypes reveal low sequence divergence and high unique mutations.
• Most Korean haplotypes were genetically isolated from their neighboring haplotypes.
• Apodemus agrarius coreae has experienced rapid population expansion.

The aim of this study was to investigate the genetic diversity and genetic structure of the striped field mouse Apodemus agrarius coreae in Korea. The Korean A. a. coreae is characterized by high levels of haplotype diversity (Hd = 0.967) and low levels of nucleotide diversity (π = 0.00683). Haplogroup 1 is well separated from the haplotypes of the neighboring regions of the Korean Peninsula, while the other haplogroups are closely related to those from the Russian Far East. Thus, further investigations are required to confirm the validity of the subspecies status of A. a. coreae by implementing additional morphological characters as well as genetic data from the populations present in the Korean Peninsula and its neighboring countries. Haplogroup 1 includes most Korean haplotypes and forms a star-like haplotype network structure, which reveals relatively low levels of sequence divergence and high frequency of unique mutations (only few mutations are shared in most of the haplotype nodes). The results indicate that the haplotypes of Haplogroup 1 might have experienced population expansion since their migration into Korea, which was further corroborated with negative results of neutrality tests for Korean population of A. a. coreae.