Okumura N, Ishiguro N, Nakano M, Matsui A, Sahara M
Department of Bioresource Chemistry, Obihiro University of Agriculture and Veterinary Medicine, Hokkaido, Japan.
Anim Genet. 1996 Dec;27(6):397-405. doi: 10.1111/j.1365-2052.1996.tb00506.x.
Mitochondrial DNA (mtDNA) major non-coding regions were amplified from 73 dogs of eight Japanese native dog breeds and from 21 dogs of 16 non-Japanese dog breeds by the polymerase chain reaction and their DNA sequences were determined. A total of 51 nucleotide positions within the non-coding region (969-972 base pairs) showed nucleotide variations of which 48 were caused by transition. These nucleotide substitutions were abundant in the region proximate to tRNA(Pro). In addition to the nucleotide substitutions, the dog mtDNA D-loop sequences had a heteroplasmic repetitive sequence (TACACGTAGCG) involving size variation. The DNA sequences of the non-coding region were classified into four different groups by phylogenetic analysis and the deepest branchpoints of this dog phylogeny was calculated to about 100,000 years before the present. Phylogenetic analysis showed that Japanese native dog breeds could not be clearly delimited as distinct breeds. Many haplotypes found in members of some clustering groups were seen in each dog breed, and interbreed nucleotide differences between Japanese dog breeds were almost the same as the intrabreed nucleotide diversities.
通过聚合酶链反应从8个日本本土犬种的73只狗以及16个非日本犬种的21只狗中扩增出线粒体DNA（mtDNA）主要非编码区，并测定其DNA序列。非编码区（969 - 972个碱基对）内共有51个核苷酸位点存在核苷酸变异，其中48个是由转换引起的。这些核苷酸替换在靠近tRNA(Pro)的区域丰富。除了核苷酸替换外，犬mtDNA D环序列还有一个涉及大小变异的异质性重复序列（TACACGTAGCG）。通过系统发育分析，非编码区的DNA序列被分为四个不同的组，并且计算出该犬种系统发育的最深分支点大约在距今10万年前。系统发育分析表明，日本本土犬种不能被明确界定为不同的品种。在一些聚类组的成员中发现的许多单倍型在每个犬种中都有出现，并且日本犬种之间的品种间核苷酸差异与品种内核苷酸多样性几乎相同。
