GENETIC-VARIATION AND GEOGRAPHIC-DISTRIBUTION ON THE MITOCHONDRIAL-DNA IN LOCAL-POPULATIONS OF THE MUSK SHREW, SUNCUS-MURINUS

The musk shrew (Suncus murinus) is widely distributed throughout Asia and East Africa. The mitochondrial DNA (mtDNA) of this species was ana lyzed in individuals from 31 local populations in nine Asian countries and Mauritius, using 17 restriction endonucleases. Although fourteen and nine mtDNA haplotypes were detected from Bangladesh and Nepal, res pectively, one to four haplotypes were found in each Southeast Asian c ountry, and one common haplotype existed in Japan, Philippines, Vietna m, Thailand and Indonesia. Clustering analysis of mtDNA haplotypes cla ssified shrew populations to three groups-continental group (Banglades h and Nepal), islands' group (insular countries and Vietnam) and Malay group. The average nucleotide diversity among these three groups was calculated to be about 3.5%. These results indicate that the origin of feral populations in this species might be old and their population s izes are extremely large in the continent, and suggest a rapid spread of this animal throughout the islands. Although we have not shown yet an evidence of close relationships between islands' and continental mt DNA haplotypes, it is likely that the musk shrew had migrated from the continent in South Asia to the islands in Southeast Asia recently.