基于线粒体12SrRNA序列研究凤鲚两个野生群体的遗传多样性

Genetic diversity in two wild populations of tapertail anchovy Coilia mystus via 12S ribosomal segment sequences of mitochondrial DNA

对凤鲚Coilia mystus长江群体和珠江群体的线粒体DNA(m itochondrial DNA,m tDNA)的12SrRNA基因片断序列进行分析。排列比对后,获得该基因365 bp的一致序列。在所测得的42个序列中,共检测到6种单倍型,其中长江群体有2种,珠江群体有4种。长江群体和珠江群体的单倍型多样性指数分别为0.5263和0.6104,核苷酸多样性指数分别为0.144%和0.192%。凤鲚长江群体内部的遗传距离为0.3%,珠江群体内部的遗传距离为0.3%～0.5%,长江群体与珠江群体之间的遗传距离为0.8%～1.4%。邻接树显示长江凤鲚和珠江凤鲚各自形成一个单系类群。AMOVA分析显示群体间的变异占总变异的82.80%,提示两者可能有相互隔离的遗传结构。

Genetic diversities in two populations of tapertail anchovy Coilia mystus, Yangtze River population and Pearl River population, were investigated by 12S ribosomal segment sequences of mitochondrial DNA. A total of forty- two individuals including twenty in Yangtze River populations and twenty -two in Pearl River population were collected. Sequences of 12S ribosomal （12SrRNA） amplified by PCR was used and 365 base pairs concensus sequences were obtained. Six different haplotypes were detected among all the 42 sequences, two in Yangtze River population and four in Pearl River population. The haplotype diversity index of Yangtze River population and Pearl River population was 0. 5263 and 0.6104, respectively. The nucleotide diversity of Yangtze River population and Pearl River population was 0. 144% and 0. 192%, respectively. Genetic distances were found to be 0.3% in the Yangtze River population, and between 0.3% and 0.5% in the Pearl River population. The genetic distances varied from 0.8% to 1.4% between the Yangtze River population and the Pearl River population. The Neighbour - Joining tree supported the two populations forming monophyletic group respectively. Analysis of molecular variance （AMOVA） analysis revealed that the variation between the populations accounted for 82.80% in total variation, suggesting that their genetic structure be isolated each other.