新疆褐牛遗传多样性和母系遗传背景分析

Analysis of Genetic Polymorphism and Maternal Genetic Backgroundof Xinjiang Brown Cattle

中文关键词: 新疆褐牛  遗传多样性  线粒体DNA D Loop  系统发育

英文关键词: Xinjiang Brown Cattle  genetic polymorphism  mtDNA D loop  phylogeny

中文摘要:

      为客观评价并挖掘新疆褐牛遗传资源和种质资源，开展了新疆褐牛及其杂交类群母系遗传背景和分 子遗传特性研究。将新疆褐牛的mtDNA D- Loop区作为遗传标记位点，开展基因组DNA PCR扩增和测序；同 时将5个引进品种和6个中国地方黄牛品种的mtDNA D- Loop区核苷酸序列作为对照，对核苷酸多态位点、单 倍型数、核苷酸多样性等指标进行分析，构建系统发育树。结果显示，碱基A和T在新疆褐牛及其杂交类群 mtDNA D- Loop区含量丰富， A、T、C、G的平均含量分别为32.75%、28.78%、24.65%和13.82%，C+G的平均 含量（38.47%）显著低于A+T的平均含量（61.53%）；检测到89处多态位点中有25处为单一多态位点，64处 多态位点为简约信息位点；界定了55种单倍型；新疆褐牛及其杂交类群与欧洲普通牛、非洲瘤牛聚为一 类。表明新疆褐牛及其杂交类群mtDNA D Loop区核苷酸变异丰富，群体变异程度较高，新疆褐牛具有多元 化的起源特点，兼具普通牛和瘤牛两个遗传背景。

英文摘要:

      In order to evaluate and excavate genetic resources and germplasm resources of Xinjiang Brown Cattle,this study investigated the genetic polymorphism and maternal genetic background of Xinjiang Brown Cattle.PCR amplification and sequencing of genomic DNA were conducted based on the marker sites within mtDNA D- Loop region.And further this study analyzed the genetic polymorphism indexes,such as nucleotide polymorphism loci,nucleotide diversity and number of haplotype of the nucleotide sequence of mtDNA D- loop of 8 indigenous yellow cattle species and 5 introduced species as control,and constructed phylogenetic tree.The mtDNA D- loop of Xinjiang Brown cattle and its hybrid populations were rich in nucleotide A and T.The average contents of A,T,C and G were 32.75%,28.78%,24.65% and 13.82%,respectively.The average content of C+G (38.47%) was significantly lower than that of A+T (61.53%).A total of 89 polymorphic sites were identified,of which 25 were single polymorphic sites and 64 were reduced information sites.Fifty five haplotypes weredefined.Xinjiang brown cattle and their hybrids belong to the same group as European common cattle and African Zebu cattle.Xinjiang Brown cattle and its hybrids were rich in nucleotide mutations and higher population variation degree.Xinjiang Brown cattle have diverse origins and possess common cattle and zebu cattle genetic backgrounds.