中国南部和西北地区山羊mtDNA D-loop区遗传多样性及群体分化

发布时间：2018-03-13 11:08

本文选题：山羊　切入点：线粒体　出处：《农业生物技术学报》2017年02期 　论文类型：期刊论文

【摘要】：家养山羊(Capra hircus)由野生山羊进化而来,我国家养山羊适应性强,分布范围广,品种资源丰富。长期的自然选择和人工选择,可能会导致南北地区家养山羊遗传多样性及分化有一定差别。为了了解中国南部地区和西北地区家养山羊遗传多样性及其起源分化,本研究对南部地区5个家养山羊品种69个个体线粒体DNA D-loop区进行了测序,结合所下载的西北地区3个品种33条山羊序列进行数据分析。结果发现,南部地区家养山羊平均单倍型多样性(haplotype diversity,Hd)和平均核苷酸多样性(nucleotide diversity,π)分别为0.954±0.005和0.019 57±0.002 10,西北地区山羊分别为0.919±0.106和0.019 08±0.001 15;不同群体的中性检验Fu′s Fs值为较大负值(P0.05),离差平方和(sum of squares of deviations,SSD)与Raggedness值统计检验均差异不显著,表明核苷酸不配对分布未偏离群体扩张模型,通过核苷酸错配分布分析发现,对于整个单倍型群体来说在13、37、61碱基处各有一个峰值;NJ(neighbor-joining)聚类分析指出,所有山羊序列共分为两大支系(A支系和B支系),南部和西北地区山羊在两支系中均有分布。结果表明,中国南部地区山羊遗传多样性略高于西北地区山羊群体,但较几年前有所下降;对于整个单倍型群体以及A、B支系来说,均经历过群体扩张,对整个群体来说至少发生过3次扩张事件;捻角野山羊(C.aegagrus)是本研究所涉及的中国南部和西北地区家养山羊的野生祖先。本研究为进一步了解中国南部与西北地区山羊起源分化以及遗传多样性提供理论支持,并为地方山羊品种保护提供理论依据。
[Abstract]:Capra hircus, a domestic goat, evolved from wild goats. The domestic goats in China have strong adaptability, wide distribution, rich variety resources, and long-term natural and artificial selection. In order to understand the genetic diversity and origin of domestic goats in southern China and northwest China, the genetic diversity and differentiation of domestic goats may be different. In this study, 69 individual mitochondrial DNA D-loop regions of 5 domestic goat breeds in southern China were sequenced, and 33 goat sequences of 3 breeds in Northwest China were analyzed. The average haplotype diversity (Hd) and the average nucleotide diversity (蟺) were 0.954 卤0.005 and 0.019 57 卤0.002 10, respectively, and 0.919 卤0.106 and 0.019 08 卤15 in the northwest region, respectively. The sum of difference square and sum of squares of deviations SSDs had no significant difference with Raggedness. The results showed that the distribution of nucleotide mismatch pairs did not deviate from the population expansion model. Through the analysis of nucleotide mismatch distribution, it was found that there was a peak value of NJJ neighbor-joining for the whole haplotype population at the nucleotide 1337nighbor-joining. All the goat sequences were divided into two branches, branch A and branch B. The results showed that the genetic diversity of goats in the south and northwest of China was slightly higher than that of the goat population in the northwest of China, and the results showed that the genetic diversity of the goats in the southern part of China was slightly higher than that of the goat population in the northwestern region. For the whole haplotype population and AHB branch, the population has experienced population expansion, and at least three expansion events have taken place for the whole population. C. aegagrus is a wild ancestor of domestic goats in the south and northwest of China. This study provides theoretical support for further understanding of the origin, differentiation and genetic diversity of goats in the south and northwest of China. It also provides theoretical basis for the protection of local goat breeds.
【作者单位】：河北北方学院动物科技学院;衡水学院生命科学学院;
【基金】：河北省教育厅高等学校科学技术研究青年基金项目(No.QN2014077)
【分类号】：S827

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