基于线粒体DNA D-loop序列分析养殖刀鲚与湖鲚的遗传多样性

以线粒体DNA D-loop全序列为分子标记,研究了灌江纳苗养殖刀鲚Coilia nasus子三代(F3)和湖鲚Coilia nasus taihuensis在淡水生活环境下两个群体的遗传多样性.结果显示:养殖刀鲚的D-loop序列长度为1 210 ～1 252 bp,湖鲚的序列长度为1 252～1 290 bp;在两个群体19个个体中,共检测到变异位点(S) 35个,其中单一多态位点14个,简约信息位点21个；有12种不同的单倍型,单倍型多态性(H)为0.924；核苷酸多样性(π)为0.0099,平均核苷酸差异数(K)为4.154；养殖刀鲚群体内的各遗传多样性参数稍高于湖鲚,说明养殖刀鲚比湖鲚的遗传多样性要丰富,保持着较高的遗传多样性；养殖刀鲚与湖鲚的平均遗传距离(0.0148)要远小于它们与七丝鲚Coilia grayi的平均遗传距离(0.0528、0.0537),同时系统发育树也表明,养殖刀鲚和湖鲚共同构成1个单系群,为两种生态型种群,尚未达到种或亚种的分化.

The genetic diversity of farmed tapertail anchovy Coilia nasus and Coilia nasus taihuensis by mitochondrial D-loop genes analysis

Genetic diversity of two genetic-ecological populations in farmed tapertail anchovy Coilia nasus and Coilia nasus taihuensis were assayed by D-loop sequence of mtDNA as a molecular maker.The complete mitochondrial D-loop gene sequences of farmed Coilia nasus was shown to be ranged from 1 210 bp to 1 252 bp and Coilia nasus taihuensis to be varied from 1 252 to 1 290 bp in length.Total of 35 variation sites including 14 singleton polymorphic sites and 21 parsimony informative polymorphic sites were defined in the 19 individuals sampled,in which 12 haplotypes were detected.The haplotype diversity（H） was found to be 0.924,nucleotide diversity（π） 0.0099,the average nucleotide difference（K） 4.154 and the average genetic distance 0.0148.There were a little higher genetic parameters and heredity diversities in the farmed Coilia nasus than those in Coilia nasus taihuensis.It was found that there was significantly smaller average genetic distance（0.0148） between farmed Coilia nasus and Coilia nasus taihuensis than that（0.0528） between each species of farmed Coilia nasus and Coilia nasus taihuensis and Coilia grayii（0.0537）.The phylogeny tree also showed that a monophyletic group was comprised of the farmed Coilia nasus and Coilia nasus taihuensis,on differentiation of species or subspecies.