条石鲷养殖群体线粒体控制区序列遗传变异分析

Genetic variation of mitochondrial control region sequences in cultured Oplegnathus fasciatus

利用线粒体控制区序列研究了条石鲷养殖群体的遗传多样性水平和遗传结构。通过PCR扩增与序列测定获得了长度为469 bp的线粒体控制区基因片段,在30个个体中共发现27处碱基变异,A、T、G、C碱基的平均含量分别为36.5%、30.2%、12.5%和20.8%,A+T含量明显高于G+C含量。30条线粒体控制区序列共定义了11个单倍型,存在27个多态性位点,产生27个突变。其中,包含简约信息位点13个,发生转换7次,颠换1次,没有发现插入或缺失现象。单倍型多样性(Hd)为0.892,核苷酸多样性(Pi)为0.013 8,平均碱基差异(K)为6.473。采用邻接法(Neighbor-joining,NJ)构建分子系统树,所有的11个单倍型被分成两个分支。结果表明,养殖条石鲷种群具有较高的遗传多样性水平,其结果可为条石鲷人工养殖及系统进化研究提供基础资料。

Genetic diversity and population structure in cultured Oplegnathus fasciatus were analyzed using a 469-bp fragment of the mitochondrial D-Loop partial sequences.A total of 27 polymorphic sites were found among 30 samples.The average content of A,T,G and C was 36.5%,30.2%,12.5% and 20.8%,respectively.And the sum content of A＋T was higher than that of G＋C.30 mitochondrial control region sequences defined 11 distinct halotypes,and 27 polymorphic sites and mutational loci were found,including 13 parsimony-informative sites,7 transition loci,1 transversion loci and no insertions and deletions were found.The mean haplotype diversity（Hd）,nucleotide diversity（Pi） and the average number of nucleotide difference（K） in the Oplegnathus fasciatus population were 0.892,0.013 8 and 6.473,respectively.Neighbor-joining（NJ） phylogenetic tree and the Unweighted Pair Group Method with Arithmetic（UPGMA） phylogenetic tree divided all 11 haplotypes into two clades.Results revealed high level of genetic diversity in cultured Oplegnathus fasciatus,providing basic information for the reproduction and phylogenetic study of this species.