高原鼠兔四个地理种群的遗传多样性与遗传分化  

Genetic diversity and differentiation in four natural populations of plateau pika (Ochotona curzoniae)

作　　者：周乐[1] 杨生妹[1] 于智勇[2] 殷宝法[1] 淮虎银[1] 李世平[1] 魏万红[1] 

机构地区：[1]扬州大学生物科学与技术学院 [2]扬州教育学院,扬州225002

出　　处：《兽类学报》2007年第3期221-228,共8页Acta Theriologica Sinica

基　　金：国家自然科学基金重大项目:青藏铁路的生态效应(90202012)资助

摘　　要：采用7个多态微卫星DNA标记分析了4个高原鼠兔地理种群(海晏种群、西大滩东种群、西大滩西种群和昆仑山种群)的遗传多样性和遗传分化。采用多态信息含量(PIC)、期望杂合度(He)、观测杂合度(Ho)、基因流(Nm)和基因分化系数(Fst)对种群及物种的遗传多样性水平进行分析;计算各种群间的遗传距离(GD)、遗传相似度(GI)以及遗传距离与地理距离的相关系数,并进行UPGMA聚类分析。研究结果显示,高原鼠兔的遗传多样性在小哺乳动物中处于较高水平,其He和Ho的平均值分别为0·5332和0·6003,其Fst为0·0975,即有9·75%的变异存在于种群之间,即变异主要存在于种群内部。4个种群间的杂合度与多态信息含量均无显著差异,说明它们的遗传多样性水平基本相当。海晏种群与其余3个种群的遗传分化均达到了中度分化水平(Fst=0·1043),而另3个种群间几乎没有分化(Fst=0·0253)。Manteltest结果表明地理距离与遗传距离间没有显著的相关性。The plateau pika（Ochotona curzoniae） has a widespread distribution over the high alpine grassland of the Qinghai-Tibet Plateau of People＇s Republic of China.It is one of the most dominant small mammals and plays an important role in keeping the balance of the alpine meadow ecosystem.The aim of this paper was to investigate the level of genetic diversity and also to test the hypothesis of IBD（isolation by distance） for this old species.Samples of plateau pikas were collected from four natural populations（Haiyan,Xidatan E,Xidatan W and Kunlunshan populations）.Genetic diversity and differentiation were assessed with seven polymorphic microsatellite markers.The genetic diversity of plateau pika was comparatively higher than that for some other small mammals（Ho =0.6003,He=0.5332）.The majority of genetic variation occurred within populations（Fst= 0.0975）.The levels of genetic diversity of the four populations were similar.High genetic differentiation was encountered between Haiyan population and the other three（Fst= 0.1043） probably due to the long distance between them.However,the results of mantel test showed that there was no significant correlation between geographical distance and genetic distance.

关 键 词：高原鼠兔 微卫星 遗传多样性 遗传分化 

分 类 号：Q958[生物学—动物学]