新疆帕米尔牦牛群体线粒体DNA的遗传多样性及系统进化分析

Analysis on Genetic Diversity and Phylogenetic Evolution of Mitochondrial DNA in Pamir Yaks

为了从分子水平上探究新疆帕米尔牦牛群体的遗传多样性、亲缘关系,为帕米尔牦牛种质资源的保护与利用提供参考依据,该研究以克孜勒陶牦牛、布伦口牦牛、吉根牦牛、哈拉峻牦牛、库兰萨日克牦牛、苏木塔什牦牛等6个帕米尔牦牛类群的111头牦牛为研究对象,测定牦牛mtDNAD-loop区序列,分析其多态性,构建系统进化树。结果表明:帕米尔牦牛mtD-NAD-loop区序列长度为895~916bp,共检测到111个变异位点,其中单态突变位点36个,简约信息位点75个;在111头个体中共检测出33种单倍型,平均单倍型多样性(Hd)、平均核苷酸多样性(Pi)分别为0.9206、0.02613;6个类群间平均遗传距离为0.027,哈拉峻牦牛与克孜勒陶牦牛间遗传距离最小(0.019)。以上结果表明,帕米尔牦牛具有丰富的遗传多样性,苏木塔什牦牛、哈拉峻牦牛是较纯的牦牛类群,其它牦牛类群在进化过程中出现相互交流的情况。

The study aimed to investigate the genetic diversity and genetic relationship of the Pamir yak populations at the molecular level,and provide reference for the protection and utilization of Pamir yak germplasm resources.In this study,111 yaks from 6 Pamir yak populations(Kizilto yak,Bulungkol yak,Jigin yak,Harajun yak,Kuransarik yak,and Sumutash yak)were used to analyze the mtDNA D-loop region sequence and its polymorphism,and to construct a phylogenetic tree.The results showed that the length of the mtDNA D-loop region of Pamir yak was 895~916 bp,and 111 mutation sites were detected,including 36 single nucleotide variant and 75 parsimonyinformative sites.A total of 33 haplotypes were detected from 111 individuals,the average haplotype diversity(H d)was 0.9206 and average nucleotide diversity(P i)was 0.02613,respectively.The average genetic distance was 0.027 among the 6 Pamir yak populations.The genetic distance between Harajun yak and Kizilto yak is the smallest(0.019).Taken together,the present results indicate that the Pamir yak has abundant genetic diversity,Sumutash yak and Harajun yak are relatively pure yak populations,and other yak populations also have gene flow with each other during the evolution process.