不同品种绵羊D-loop区遗传多样性研究  

Genetic Diversity of Mitochondrial DNA D-loop Region in Different Breeds of Sheep

作　　者：肖帆 张利平[1] 朗侠 吴建平[2] 张筱艳[1] 靳继鹏 XIAO Fan;ZHANG Liping;LANG Xia;WU Jianping;ZHANG Xiaoyan;JIN Jipeng(College of Animal Science and Technology,Gansu Agricultural University,Lanzhou 730070,China;Institute of Animal and Pasture Science and Green Agriculture,Gansu Academy of Agricultural Science,Lanzhou 730070,China)

机构地区：[1]甘肃农业大学动物科学技术学院,兰州730070 [2]甘肃省农业科学院畜草与绿色农业研究所,兰州730070

出　　处：《西北农业学报》2021年第8期1122-1129,共8页Acta Agriculturae Boreali-occidentalis Sinica

基　　金：公益性行业(农业)科研专项(201303062)。

摘　　要：线粒体DNA(Mitochondria DNA,mtDNA)D-loop区的进化速度快且多态性丰富,因此在生物的遗传多样性和起源进化研究中具有重要意义。采用PCR扩增和基因测序的方法分析甘肃高山细毛羊(G)、欧拉羊(O)、杜泊羊(D)、蒙古羊(M)、小尾寒羊(S)和湖羊(H)的线粒体DNA D-loop区遗传多样性和进化关系。结果显示,试验羊D-loop区中GC含量低于AT含量,共检测到171个变异位点,单一多态位点58个,简约信息位点113个,共87个单倍型,单倍型多样度(Hd)分别为0.993、1.000、0.968、1.000、0.933和1.000,核苷酸多样度(Pi)分别为0.02237、0.01463、0.01193、0.01747、0.02140和0.02348,湖羊的平均核苷酸差异度最大(K=31.622),而杜泊羊最小(K=15.995)。蒙古羊和杜泊羊的核苷酸平均差异数Kxy最大,蒙古羊和欧拉羊的核苷酸平均差异数Kxy最小。核苷酸歧异度Dxy与核苷酸平均差异数Kxy结果一致。系统发育树结果显示,湖羊与小尾寒羊先聚集在一起,然后与杜泊羊聚为一类;欧拉羊与蒙古羊先聚为一类,然后与甘肃高山细毛羊聚为一大类,说明湖羊与小尾寒羊遗传差异小。Mitochondrial DNA D-loop region plays an important role in genetic diversity and evolution of organisms because it is rich in polymorphism and has fast evolution velocity.To explore the relationship of mitochondrial DNA D-loop region between genetic diversity and evolution in different breeds of sheep by PCR amplification and gene sequencing,Gansu alpine fine wool sheep(G),Oula sheep(O),Dorper sheep(D),Mongolian sheep(M),Xiaoweihan sheep(X)and Hu sheep(H)were analyzed.The results showed that the CG content in D-loop region was lower than AT content,and there were 171 variable sites(58 Singleton variable sites and 113 parsimony informative sites)and 87 haplotypes in all sheep mitochondrial DNA D-loop region.Haplotype diversity(Hd)was 0.993,1.000,0.968,1.000,0.933 and 1.000,and nucleotide diversity(Pi)was 0.02237,0.01463,0.01193,0.01747,0.02140 and 0.02348,respectively.The largest average number of nucleotide differences was in Hu sheep(K=31.622)and the least was in Dorper sheep(K=15.995).The largest Kxy value of average nucleotide differences were between Mongolian sheep and Dorper sheep,and the least Kxy value were between Mongolian sheep and Oula sheep.The Dxy value of nucleotide diversity was consistent with the Kxy value of average nucleotide differences.The results of phylogenetic tree showed that there were two major sample clusters,at first level,the Hu sheep and Xiaoweihan sheep were comprised of one sub-cluster and Dorper sheep joined this group to be constituted another sub-cluster,at other level,Oula sheep and Mongolian sheep were comprised of one sub-cluster and Gansu alpine fine wool sheep joined this group to be constituted another sub-cluster.In conclusion,the Hu sheep and Xiaoweihan sheep,Mongolian sheep and Oula sheep have less genetic divergence.

关 键 词：绵羊 线粒体DNA D-loop 遗传多样性 

分 类 号：S826[农业科学—畜牧学]