Variations in Mitochondrial DNA of Dogs Isolated from Archaeological Sites in Japan and Neighbouring Islands.

Abstract

equences of ancient mitochondrial DNA (mtDNA) from archaeological remains of Japanese dogs were determined from 145 ancient dog samples (mainly bones) from the Jomon (100C-4C B.C.), Yayoi (4C B.C.-3C A.D.), Kofun (3-6C A.D.), Okhotsk (7-12C A.D.) and the Kamakura (12-14C A.D.) Periods.Highly variable sequences of the mitochondrial control region (198 base pairs) were amplified at least twice from independently prepared DNA extracts, and those from ancient samples were compared with 28 haplotypes from 178 modern dogs.The 198-bp ancient mtDNA was amplified from 74 ancient dog samples, and the sequences were classified into 19 haplotypes comprising five modern haplotypes (M1, M2, M5, M10 and M11) identified in modern dogs and 14 ancient haplotypes showing unique sequences not observed in modern dogs.Haplotype M5 was widely distributed in archaeological sites in northern Japan and Sakhalin, while haplotype M2 was detected from archaeological sites in southern Japan.Three major clusters (CL1 to CL3) were distinguished within the modern dog control region using phylogenetic analysis;all ancient dogs belonged to the CL1 cluster.From these results, we could not discern which modern Japanese dog breed closely resembles ancient dogs using phylogenetic analysis, but the CL1 cluster was likely distributed in the Japanese archipelago from the Jomon Period.