Zhang J J, Duan J R, Zhou Y F, Peng J Y, Fang D A
Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, Jiangsu, China.
Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, Jiangsu, China.
Genet Mol Res. 2017 Mar 16;16(1):gmr-16-01-gmr.16019457. doi: 10.4238/gmr16019457.
Coilia ectenes is a commercially important fishery species in China. C. ectenes taihuensis is an endemic and dominant species found in Taihu Lake of China. When compared with C. ectenes, C. ectenes taihuensis lacks anadromous behavior, and can independently grow and reproduce in Taihu Lake. In this study, the mitochondrial DNA control region (D-loop) sequences were employed to investigate the genetic diversity and population structure of C. ectenes taihuensis. Sixty-eight individuals collected from 4 localities in Taihu Lake were examined. Results indicated that in the 887-bp D-loop region, seventy-seven (8.68%) sites were variant, contributing to 53 distinct haplotypes. Although the population haplotype diversity (Hd = 0.971 to 1.000) was generally high, the nucleotide diversity (π = 0.616 to 0.731%) was relatively low among the 4 populations. Additionally, the genetic distances ranged from 0.62 to 0.74% within the populations and from 0.67 to 0.74% between the populations. The neighbor-joining tree indicated that a distinct distribution of phylogenetic structure existed among haplotypes. Analysis of molecular variance and F statistics suggested that a divergence existed among populations in 4 localities, indicating that gene communication might have occurred among those populations. Furthermore, neutral tests and analysis of mismatch distribution reflected that C. ectenes taihuensis might have undergone a population expansion during the evolution process. Our study showed the population genetic diversity and structure of C. ectenes taihuensis. Results from this study might be helpful in the development and protection of fishery resource within the localities in Taihu Lake in future.
刀鲚是中国一种具有重要商业价值的渔业物种。太湖新银鱼是中国太湖特有的优势物种。与刀鲚相比，太湖新银鱼缺乏溯河洄游行为，能在太湖独立生长和繁殖。本研究采用线粒体DNA控制区（D-loop）序列来研究太湖新银鱼的遗传多样性和种群结构。对从太湖4个地点采集的68个个体进行了检测。结果表明，在887 bp的D-loop区域中，有77个（8.68%）位点发生变异，产生了53种不同的单倍型。虽然种群单倍型多样性（Hd = 0.971至1.000）总体较高，但4个种群间的核苷酸多样性（π = 0.616至0.731%）相对较低。此外，种群内的遗传距离在0.62%至0.74%之间，种群间的遗传距离在0.67%至0.74%之间。邻接树表明单倍型间存在明显的系统发育结构分布。分子方差分析和F统计表明4个地点的种群间存在分化，表明这些种群间可能发生了基因交流。此外，中性检验和错配分布分析反映出太湖新银鱼在进化过程中可能经历了种群扩张。我们的研究揭示了太湖新银鱼的种群遗传多样性和结构。本研究结果可能有助于未来太湖地区渔业资源的开发和保护。
