基于COⅡ基因的我国海域4个长蛸群体的遗传变异分析研究 计算机科学与技术专业VIP专享

摘 要采用PCR扩增技术对中国4 个不同海域（山东青岛、浙江温州、浙江舟山、福建东山）的长蛸群体的COII基因片段进行了扩增和测序，获得了长度为560bp 长度的同源序列，分析了不同海域群体内和群体间的遗传变异。结果表明，89个个体共有28个单倍型，其中青岛群体8 个，舟山群体7 个，温州群体6 个，东山群体7 个。通过序列比对，变异均匀地分布于序列各个区域，但密码子偏好不明显。总群体单倍型多样性指数（H ）0.884±0.018 ，核苷酸多样性指数（Pi）0.10640±0.00656 ，平均核苷酸差异数（K ）57.348，显示出一定的遗传多样性。采用MEGA3.1 对4 个海域的长蛸群体进行聚类分析，构建系统树，结果表明：青岛、舟山2个群体由于遗传距离较近首先聚为一支，而与东山群体遗传关系较远，与温州群体亲缘关系最远而最后聚类。Tajima’s D 和Fu’s FS 检验显示温州群体可能经历过种群扩张，而其它3个群体可能未经历过历史扩张事件。我国海域长蛸的这种遗传结构的形成原因还有待于进一步证实。通过本次研究，从线粒体DNA水平分析我国不同海域长蛸群体的遗传变异情况，期望为开展我国长蛸群体的资源评价、物种保护及分子标记育种提供基础资料。关键词：长蛸；线粒体基因；COⅡ 基因；遗传变异AbstractFragments of COII gene were amplified and sequenced.in Octopus variabilis samples from 4 our different sea areas in China (Qingdao, Wenzhou, Zhoushan, Fujian) A 560bp aligned sequence were obtained and analyzed to detect genetic variation within and among the groups. The results showed that 89 individuals produce a total of 28 haplotypes, with eight in Qingdao group, seven in Zhoushan group, six in Wenzhou group, seven in Dongshan group. By sequence alignment, the variation is evenly distributed in the various regions of the sequence, but the codon bias is not obvious. The total population haplotype diversity index (H) is 0.884 ± 0.018, nucleotide diversity index (Pi) is 0.10640 ± .00656, the average number of nucleotide differences (K) is 57.348, showing a certain degree of genetic diversity. A phylogenetic tree among the...