Genetic variation of the mitochondrial DNA cytochrome b region in Japanesenative dog breeds (Canis familiaris)

Partial sequences (454 bases) of the mitochondrial DNA (mtDNA) cytochrome b gene (cyt b) were determined for 94 dogs including 73 Japanese native anim als. Thirteen nucleotide positions of this region showed nucleotide substit utions, which were all transitions. Three of 13 nucleotide substitutions we re nonsynonymous. A total of 14 cyt b haplotypes were found, but the Japane se native dog breeds could not be differentiated as distinct clusters in ph ylogenetic trees. These results support the previous view that genetic vari ations observed among Japanese native dog breeds could have resulted from i nterbreeding and/or intrabreeding.