利用mtDNA D-loop序列为遗传标记分析槟榔江水牛的群体遗传特征  

Analysis of Genetic Characterization of Binglangjiang Buffalo Using mtDNA D-loop Sequences

作　　者：苗永旺[1] 李大林 袁峰[1] 梁建平[1] 李卫真[1] 刘伟[1] 李卓然[1] 章纯熙[3] 

机构地区：[1]云南农业大学动物科学技术学院,云南昆明650201 [2]云南巴福乐水牛技术研究所,云南昆明650021 [3]中国农业科学院水牛研究所,广西南宁530001

出　　处：《云南农业大学学报》2011年第5期625-632,共8页Journal of Yunnan Agricultural University

基　　金：云南省应用基础研究重点项目(2007C0003Z);国家自然科学基金项目(30660024);云南省应用基础研究计划面上项目(2006C0034M;2007C057M)

摘　　要：槟榔江水牛是近年在云南西部发现的中国第一个本土河流型水牛群体,具有较高种用价值,但其重要遗传背景信息还不清楚。本文采用PCR产物直接测序法对86头槟榔江水牛mtDNA D-Loop序列进行了突变检测,并以GenBank上已发表的70条河流型和112条沼泽型水牛mtDNA D-Loop序列为对照,对所得数据进行群体遗传和系统发育分析。结果在槟榔江水牛中检测到33种单倍型,112个多态位点。其中单一变异位点14个,简约信息位点98个。槟榔江水牛mtDNA D-Loop序列T,C,A,G的平均含量分别为28.43%,24.82%,31.96%,14.79%,单倍型多样度为(0.948±0.012),核苷酸多样度为(0.038 1±0.001 6),序列间平均核苷酸差异数为33.288,群体内平均遗传距离为(0.043±0.005)。系统发育、中介网络图和群体遗传关系分析表明,槟榔江水牛含有两个差异显著的母系世系组分,其中一个为河流型世系,在群体中占61.63%;另一个为沼泽型世系,在群体中占38.37%,而其沼泽型世系可进一步分为A,B,C 3个支系,其中,C为在水牛中新发现的支系,其频率极低。结果揭示了槟榔江水牛群体遗传多样性丰富,但该群体存在一定的沼泽型水牛基因渗入。Binglangjiang buffalo(BLJ)is the first indigenous river type buffalo found in western Yunnan province in China recent years.It possesses high breeding value,but its important genetic background information is unclear.In this study,we examined mitochondrial DNA D-loop sequence variation of 86 BLJ samples by the method of PCR product direct sequencing.Pooled the sequences with 70 river buffalo and 112 swamp buffalo sequences published in GenBank database as control,we have conducted population genetic and phylogeny analysis.A total of 33 mitochondrial haplotypes with 112 polymorphic sites included 14 singleton polymorphic sites and 98 parsimony informative sites were detected in BLJ.The average frequencies of T,C,A and G for the sequences of BLJ were 28.43%,24.82%,31.96% and 14.79%,respectively.And haplotype diversity,nucleotide diversity,the average number of nucleotide differences and the average genetic distance within BLJ population were(0.948±0.012),(0.038 1±0.001 6),(33.288,0.043±0.005),respectively.Phylogenetic and median-joining network and genetic divergence analysis revealed that there were two big distinct maternal lineages identified in BLJ population,in which one was river buffalo lineage accounted for 61.63% in the population,another was swamp buffalo lineage accounted for 38.37% in the population.And swamp buffalo lineage in BLJ further fell into three lineages(A,B and C),in which lineage C was new lineage found in buffalo with low frequency.The results indicate that there is very high genetic diversity in BLJ population which is under the condition of genetic admixture with swamp buffalo.

关 键 词：槟榔江水牛 MTDNA D-LOOP 遗传多态性 遗传分化 基因渗入 

分 类 号：S823.83[农业科学—畜牧学]