基于线粒体16S rRNA基因序列的中日朝菲律宾蛤仔野生群体遗传多样性分析

Genetic diversity analysis of wild populations of Manila clam Ruditapes philippinarum from China,Japan and Democratic People's Republic of Korea based on mitochondrial 16S rRNA gene sequence

为了解中国菲律宾蛤仔Ruditapes philippinarum野生苗种产区的群体和潜在可作修复用途的日本、朝鲜群体的种质遗传基础,以中国山东莱州(LZ)、广西北海(BH)、辽宁营口(YK)、天津(TJ)4个野生群体,以及日本北海道(JH)和朝鲜新义州(NKS)野生群体(各10个)为材料,通过线粒体16S rRNA基因片段扩增测序,比较了各群体的遗传结构和遗传多样性。结果表明:菲律宾蛤仔16S rRNA序列扩增片段为535 bp,基因片段的T、C、A、G含量分别为33.3%、10.9%、33.8%和22.0%,A+T含量为67.1%,60个个体共确定了20个单倍型,不同个体间存在单倍型共享现象;6个群体的单倍型多样性(Hd)为0.378~0.911,核苷酸多样性(P_(i))为0.00075~0.01060,核苷酸差异数(K)为0.400~5.578;菲律宾蛤仔中国天津、营口、莱州及北海4个群体具有较丰富的遗传多样性,朝鲜新义州和日本北海道群体遗传多样性(H_(d)<0.5,P_(i)<0.005)较低。研究表明,中日朝菲律宾蛤仔野生群体可划分为南、北方谱系,即北海群体为南方谱系,其他5个群体为北方谱系,中国北方的3个群体(营口、天津和莱州)及日本、朝鲜群体间存在距离隔离模式基因流,中国人工异地移养菲律宾蛤仔活动对本地野生群体基因资源产生一定影响,本研究结果可为菲律宾蛤仔种质资源保护和可持续利用提供参考。

The genetic structure and genetic diversity were compared and analyzed in wild populations of Manila clam Ruditapes philippinarum collected from Laizhou(LZ),Beihai(BH),Yingkou(YK),and Tianjin(TJ),China,from Hokkaido,Japan(JH)and Sinuiju(NKS),Democratic People's Republic of Korea(D.P.R.Korea),by amplification and sequencing of mitochondrial 16S rRNA gene fragment to investigate the genetic diversity and genetic differentiation in wild Manila clam in coastal areas of China,Japan and D.P.R.Korea.The results showed that the Manila clam had 16S rRNA sequence amplification fragment of 535 bp,with the contents of 33.3%in T,10.9%in C,33.8%in A,22.0%in G,and A+T of 67.1%.A total of 20 haplotypes were identified from 60 individuals,haplotype sharing among different individuals.There were haploid type diversity(Hd)of 0.378-0.911,nucleotide diversity(P_(i))of 0.00075-0.01060,and nucleotide differences(K)number of 0.400-5.578 in the six wild populations of Manila clam,with relatively rich genetic diversity in the four populations of Manila clam in Tianjin,Yingkou,Laizhou and Beihai,and with relatively low genetic diversity in the populations of Sinuiju and Hokkaido(H_(d)<0.5,P_(i)<0.005),indicating that the six groups of Manila clam were divided into north and south lineages,that is,the North Sea group was the south lineages,and the other five groups were the north lineages.The gene flow of distance-isolated pattern was found among the three populations in northern China,Japan and D.P.R.Korea.In China,the transplanting of Manila clam has a certain influence on the genetic resources of local wild populations.This finding provides reference with the conservation and sustainable utilization of the germplasm resources of Manila clam.