Objective To understand the genetic diversity of Pomacea population in Guangxi by analyzing CO I genes.
Methods The samples of Pomacea were collected from Nanning, Guilin, Hezhou, Baise and Chongzuo. CO I gene of samples amplified using PCR were sequenced. The haplotypes obtained in this study and those in GenBank were used to construct phylogenetic tree by using the neighbor-joining method in MAGE 7.0, and the genetic distance between samples was calculated to analyze their genetic diversity.
Results The CO I gene was 493 bp in length. Two haplotypes were identified from 11 samples: haplotype-1 and haplotype-2. The samples ( n=9) with haplotype-1 were derived from Hengxian of Nanning ( n=2), Fuchuan County of Hezhou ( n=1), Lipu County of Guilin ( n=1), Tianlin County of Baise ( n=2) and Pingxiang County of Chongzuo ( n=3); The samples ( n=2) with haplotype-2 were derived from Hengxian County of Nanning and QuanzhouCounty of Guilin respectively. The data showed that samples with haplotype-1 is genetically closest to P. canaliculata (genetic distance: 0.047), whereas samples with haplotype-2 is genetically closest to P. insularum (genetic distance: 0.062). The evolutionary tree constructed according to the above conditions formed 7 branches, namely P. canaliculata, P. camena, P. insularum, P. paludosa, P. diffusa, P. haustrum, and outgroup Pilaconica. Haplotype 1 and P. canaliculata from Hawaii (GenBank Accession No: EU 523129) formed a branch, haplotype 2 and P. insularum from Brazil (GenBank Accession No: EF514942) formed a branch, with confidence values above 98%.
Conclusion It is preliminarily judged that there are two types of Pomaceas pp. in Guangxi, including P. canaliculata and P. insularum, and no genetic differentiation was found in the population.
摘要： 目的 通过对广西不同地区福寿螺的 COⅠ基因进行分析, 以了解广西福寿螺种群的遗传多态性。 方法 从南宁市横县、桂林市全州县和荔浦县、贺州市富川县、百色市田林县和崇左市凭祥县共计6个县区采集福寿螺样本, 提取DNA并进行 COⅠ基因的PCR扩增及测序。运用MAGE 7.0将本研究获得的单倍型与GenBank中的福寿螺单倍型使用邻接法构建系统进化树, 并计算个体间的遗传距离, 分析其遗传多样性。 结果 COⅠ基因长度为493 bp, 从11个样本鉴定出2种单倍型：单倍型1 (Haplotype 1) 和单倍型2 (Haplotype 2) 。其中9个样本为Haplotype 1, 分别来源于南宁市横县 (2个) 、贺州市富川县 (1个) 、桂林市荔浦县 (1个) 、百色市田林县 (2个) 、崇左市凭祥县 (3个), 该单倍型与小管福寿螺遗传距离最近, 为0.047; 2个样本为Haplotype 2, 分别源自为南宁市横县和桂林市全州, 与孤岛福寿螺遗传距离最近, 为0.062。根据上述条件所构建的进化树形成了7个分支, 分别为 P. canaliculata、 P. camena、 P. insularum、 P.paludosa、 P. diffusa、 P. haustrum、和外群 Pilaconica。Haplotype 1与来自美国夏威夷 (GenBank登录号EU 523129) 的 P.canaliculata组成一个分支, Haplotype 2与来自巴西 (GenBank登录号EF514942) 的 P. insularum组成一个分支, 且置信值均在98%以上。 结论 初步判断广西地区存在小管福寿螺与孤岛福寿螺两种类型的福寿螺, 其种群内没有发现遗传分化。