基于线粒体控制区序列变异分析宁夏六盘山地区甘肃鼢鼠遗传多样性

宁夏六盘山地区是甘肃鼢鼠的典型分布区，本研究旨在探讨宁夏境内六盘山地区甘肃鼢鼠遗传多样性及其遗传分化。通过测定甘肃鼢鼠线粒体DNA控制区全序列，分析了六盘山地区6个不同地理种群甘肃鼢鼠遗传多样性与遗传结构。获得了长度为894~897 bp的D-loop序列，定义了20种单倍型，共检出72个变异位点，整体的平均单倍型多样性高（Hd=0.988±0.016）、核苷酸多样性高（Pi=0.022 94±0.001 47）。6个地理种群之间地理距离与遗传距离呈极显著正相关关系（P<0.01）。歧点分布和中性检验均说明宁夏甘肃鼢鼠种群数量保持稳定。基于最大似然法（ML）和贝叶斯法（MB）构建的分子系统进化树表明，6个地理种群，得到3个稳定的分支。泾源、固原和隆德种群聚为一支，海原和西吉种群聚为一支，彭阳种群形成独立的进化分支。结果表明，宁夏六盘山地区甘肃鼢鼠各地理种群间因地理隔离及气候、地形的差异产生了较明显的分化，呈现出了较明显的地理分布格局。

Genetic Diversity Analysis of Eospalax cansus (Rodentia:Spalacidae) in Liupan Mountain of Ningxia Based on Mitochondrial Control-Region Sequences

Liupan Mountain of Ningxia is the typical distribution area of Gansu zokor (Eospalax cansus).The objective of this study was to discuss the genetic diversity and differentiation among Gansu zokors in Liupan Mountain of Ningxia.The genetic diversity and genetic structure of E.cansus were analyzed by measuring the complete mitochondrial D-loop DNA sequences from six populations.Among all the obtained D-loop (894-897 bp) sequences,20 haplotypes were defined and 72 variable sites were detected.The analysis indicated that the population had high haplotype diversity (Hd=0.988±0.016) and nucleotide diversity (Pi=0.022 94±0.001 47).The results showed a significantly positive correlation relationship between the genetic distance and geographic distance of six populations (P<0.01).Mismatch distributions and neutral tests demonstrated that the amounts of 6 populations were stable in Ningxia.The phylogenetic trees constructed by maximum likelihood method (ML) and Bayesian method (MB) showed that 6 geographical populations could be divided into 3 large clades.Jingyuan,Yuanzhou,Longde populations formed the monophyletic clades,Haiyuan and Xiji populations gathered together,and Pengyang group alone formed the monophyletic clade.The results indicated that there was an obvious differentiation among the geographical populations of Gansu zokors because of geographical isolation and the differences in climate and terrain,and it presented an obvious level of geographical distribution pattern.