Population history and distribution change of the Japanese macaques inferred from genetic vanations

研究了日本猕猴母系遗传线粒体DNA的地理变异。对81个地点的105个样本进行了D-loop区412个碱基的测序分析，发现了43个单倍型。他们被分为两大组，东部组和西部组。他们的边界位于Kinki和Chugoku区之间的边界附近。作为一个特例，关东地区冈山和七步地区的种群表现出明显的类型，与西部地区的种群接近。总体来说，mtDNA变异的分布受到特定地理范围的限制。在东北地区，这种类型异常统一。东部猕猴单倍型间的核苷酸替换数量低于西部，说明东部和西部猕猴种群历史上的差异。由于线粒体DNA变异的地理范围将通过社会群体的分裂而改变，线粒体DNA多样性的低程度可能表明日本东部祖先种群最近的扩张，可能是在最后一次冰川时期之后。东北地区mtDNA型的均匀分布可能是由于冰期后气候和植被条件的变化而向北再次入侵的结果。

Geographic variations of maternally inherited mitochondrial DNA were examined for the Japanese macaque. Sequencing analysis of 412 bp in the D-loop region for 105 samples from 81 localities revealed 43 haplotypes. They were classified into two major groups, eastern and western groups. Their border was located near the border between the Kinki and Chugoku districts. As an exceptional case, the populations from Okutama and Chichibu area in the Kanto district showed distinct types which were close to those in the western group.In general, the distribution of mtDNA variation was restricted to particular geographic range. The type was unusually uniform in the Tohoku district. The number of nucleotide substitutions among the haplotypes was smaller in east than in west, suggesting difference in population history between monkeys in east and west. As geographic range of mtDNA variations is to be changed through the fission of social groups, low degree of mtDNA diversity may indicate recent expansion of ancestral population in eastern part of Japan, probably after the last glacial period. The uniform distribution of mtDNA type in the Tohoku district may result from re-invasion to north succeeding to the postglacial change of climatic and vegetational conditions.