河流可能会阻碍陆生动物的迁移并导致其遗传分化,很多研究证明了河流屏障假说,但是也有少数研究不支持这个假说。本研究采集了云南省384只黄胸鼠Rattus tanezumi样本,分别来自于被5条主要河流隔开的6个地理区域。通过对mt DNA和IRBP两个基因的测序分析,检验云南省主要河流对黄胸鼠种群遗传格局的影响。共鉴定得到81个mt DNA单倍型和135个IRBP单倍型,其中很多单倍型都被2个或2个以上区域共享。AMOVA分析显示,大多数的变异源于种群内部或种群之间,只有少数变异(〈15%)源于6个区域之间。SAMOVA分析将mt DNA种群分成了3组,但每一组都被2个或2个以上的区域共享;对IRBP的分析则没有检测到明显的谱系地理结构。结果表明,河流屏障对黄胸鼠的遗传格局几乎无影响。
Rivers may hinder population migration and promote genetic differentiation of terrestrial animals. Most studies testing the riverine barrier hypothesis have yielded positive results,while very few studies do not support this hypothesis. In this study,384 Asian house rats( Rattus tanezumi) were collected from Yunnan,China. By combined use of the sequence markers of mitochondrial( mtDNA) and nuclear( IRBP),the influence of five local rivers on the population genetics of R. tanezumi was tested. A total of 81 mtDNA haplotypes and 135 IRBP haplotypes were determined,and many of which were shared by two or more of the six geographic regions. AMOVA analyses showed that most variations happened either within populations or among populations,while very few variations( 〈15%) happened among the six geographic regions formed by the five rivers. SAMOVA analysis classified the mtDNA sequences into three groups,while no genetic differentiation was detected on IRBP. Our results concluded that riverine barriers in the study area had little influence on the genetic structure of R. tanezumi.