安徽淮河水系黄鳝群体遗传多样性及其遗传结构

Genetic diversity and population structure of Monopterus albus in the Huaihe river basin of Anhui Province

利用线粒体Cyt b基因全序列（1138 bp）对安徽淮河水系黄鳝6个地理群体（阜南Fn、颍上Ys、平圩Pw、怀远Hy、凤阳Fy、明光Mg）165个样品进行遗传多样性和遗传结构分析。共检测到变异位点74个、单倍型25个,平均A＋T含量（54.8%）显著大于G＋C（45.2%）含量。平均单倍型多样性和平均核苷酸多样性分别为0.787、0.01882。各群体的遗传分化指数FST为0.01933～0.81352、基因流Nm为0.11461～26.36650,分子方差分析（AMOVA）显示44.1%的变异来自群体间,表明淮河水系黄鳝地理群体间存在较高程度的遗传分化。单倍型系统进化树和进化网络图揭示安徽淮河黄鳝6个群体的个体组成2个遗传差异明显的谱系。错配分布和中性检验结果表明安徽淮河黄鳝群体历史上较为稳定,无明显群体扩张。

The Genetic diversity and genetic structure of 6 populations ofMonopterus albus from Huaihe river basin in Anhui Province were investigated using the mitochondrial Cyt b gene （1138 bp）. We observed 74 mutations of nucleotide acids and 25 haplotypes in 165 samples. The average haplotype diversity and nucleotide diversity are 0.787, 0.01882, respectively. The A＋T content are significantly greater than G＋C content in base composition. The results of genetic differentiation index （Fsr=0.01933-0.81352）, gene flow （Nm=0.11461-26.36650） and analysis of molecular variance （AMOVA） revealed significant genetic differentiation among populations. The phylogenetic tree and statistical parsimony network based on haplotypes indicated that there are 2 distinct lineages in 6 populations. Non-significant negative value in neutrality tests and a rnultimodal distribution in the mismatch distribution analysis suggested that there was no significant expansion in the population in recent history.