细鳞斜颌鲴三个群体线粒体COⅡ基因的遗传变异

Genetic variation of mtDNA COⅡ gene in three populations of Plagiognathops microlepis

应用线粒体COⅡ基因序列分析了细鳞斜颌鲴(Plagiognathops microlepis)三个群体(梁子湖群体、龙窝湖群体和淮河群体)的遗传变异关系。结果显示:测序得到细鳞斜颌鲴线粒体COⅡ基因大小为681 bp,A+T含量(56%左右)明显高于G+C含量。三个群体18个个体共测出5种单倍型,42个核苷酸变异位点,多态位点百分率为6.17%。梁子湖群体含4种单倍型、6个变异位点,核苷酸多样性指数为0.004036,核苷酸多样性较丰富;龙窝湖群体和淮河群体各自只有1种单倍型,无变异位点。梁子湖-龙窝湖、淮河-梁子湖、淮河-龙窝湖群体间的遗传距离分别是0.002707、0.058901和0.059131。梁子湖-龙窝湖群体间遗传关系较近,而淮河-梁子湖、淮河-龙窝湖群体间亲缘关系较远。

Genetic variations of three populations （Liangzi Lake population, Longwo Lake population and Huaihe Rive population） of Plagiognathops microlepis were studied by sequence analysis of mitochondrial cytochrome oxidase subunit Ⅱ （COⅡ） gene. Gene fragments of 681 bp were acquired by PCR and DNA sequencing technique. There were 5 haplotypes, 42 nucleotide variable sites and 6. 17% of nucleotide polymorphic loci among three populations of P. microlepis. As to base composition, the contents of A ＋ T （ about 56% ） was obviously higher than that of C ＋ G. Higher nucleotide diversity was observed in Liangzi Lake population （4 haplotypes, 6 nucleotide variable sites and 0. 004036 of index of nucleotide diversity） , while no nucleotide variable site was detected in Longwo Lake population and Huaihe Rive population （only 1 haplotype respectively）. Genetic distance between populations of Liangzi Lake and Longwo Lake, Huaihe Rive and Liangzi Lake, Huaihe Rive and Longwo Lake was 0. 002707, 0. 058901 and 0. 059131, respectively. There was a closer genetic relationship between Liangzi Lake population and Longwo Lake population than that between Huaihe Rive population and other two populations.