中国沿海7个长蛸(Octopus variabilis)群体COI基因的遗传变异研究  

GENETIC VARIATION IN DIFFERENT POPULATIONS OF OCTOPUS VARIABILIS IN CHINA COASTAL WATERS BASED ON THE COI GENE ANALYSIS

作　　者：常抗美[1] 李焕[1] 吕振明[1] 迟长凤[1] 

机构地区：[1]浙江海洋学院海洋科学学院浙江省海洋养殖装备与工程技术重点实验室,舟山316004

出　　处：《海洋与湖沼》2010年第3期307-314,共8页Oceanologia Et Limnologia Sinica

基　　金：国家科技支撑计划项目;2007BAD43B00号

摘　　要：采用线粒体DNA细胞色素氧化酶亚基I(COI)基因序列测定技术分析了中国沿海重要经济头足类长蛸7个野生群体的种群遗传结构及其变异。结果表明,我国长蛸资源存在相对丰富的遗传多样性,635bp长度的核苷酸片段共检测到74个多态位点,多态位点比例达11.7%,检测的108个个体中共获25个单倍型,单倍型多样性指数(H)达0.342—0.934,平均核苷酸多样性指数(Pi)达0.0008—0.0055,高于多数海洋头足类的遗传变异。对7个群体的遗传结构进行检测表明,我国的长蛸群体间存在显著的遗传分化(P<0.05),遗传结构基本符合脚踏石模型。7个群体可明显聚类为3个类群,类群间分化系数Fst达0.8858(P<0.01),基因流大大小于1;AMOVA检测和单倍型网络关系图也证实了上述类群的分化。遗传距离分析表明,由厦门群体组成的类群与其它2类群间的遗传距离达到0.086—0.098,可能达到了亚种的分化。In this paper,genetic variation of seven populations of Octopus variabilis in China coastal waters were investigated by applying mitochondrial gene sequencing technology.Results showed that,compared with other cephalopod species,O.variabilis showed higher genetic diversity.Seventy-four polymorphic sites were detected in 635bp aligned sequence,which represented for 11.7% of the total length of the sequenced COI gene.Twenty-five haplotypes were detected out of 108 individuals from these seven populations.The haplotype diversity （H）,the mean nucleotide diversity （Pi） and the average number of nucleotide differences （K） reached 0.342—0.934,0.0008—0.0055 and 0.483—3.495,respectively.Molecular variance analysis revealed a strong genetic structure in these O.variabilis populations （P0.05）.A pattern of genetic-isolation-by-distance,conforming to the Stepping Stone Model,was detected when Nm was plotted against geographic distance.According to the UPGMA phylogenetic tree,these O.variabilis populations can be divided into three lineages.One lineage is consisted of the Dalian,the Yantai,the Qingdao,the Lianyungang and the Zhoushan population;the other one of the Wenzhou population;and the third one of the Xiamen population.Among these lineages,14—59 fixed nucleotide sites and 2 fixed amino acid sites substitute along the gene sequence and coded protein were detected.The Fst between them reached 0.8858 （P0.01）,and the Nm between them turned out to be much lower than 1.The genetic distance among the Xiamen lineage and other two lineages reached 0.086—0.098,indicating that they are different subspecies.The benthic lifestyle of O.variabilis and complicated geohistorical factors from pleistocence may influence the genetic differentiation of O.variabilis.These findings of genetic variation of O.variabilis will contribute to better exploitation and refined management of this precious cephalopod resource along the China coast in future.

关 键 词：长蛸 细胞色素氧化酶亚基I 遗传变异 

分 类 号：Q953[生物学—动物学]