翘嘴鳜EST-SSR标记的开发及3个群体遗传多态性分析

Isolation and characterization of polymorphic EST-SSRs markers in three Siniperca chuatsi population

为保护野生翘嘴鳜(Siniperca chuatsi)的种质资源以及遗传育种,本研究从翘嘴鳜的EST文库中开发微卫星并筛选出22对具有多态性的微卫星标记,对来自陆水水库(赤壁)和沅江流域(常德、怀化)的3个野生群体进行了遗传多样性分析.实验结果显示,这些标记在3个群体中均表现出了丰富的多态性;共检测到134个等位基因;各基因座观测等位基因数4～8个;平均等位基因数为6.090 1;观测杂合度0.675 4;期望杂合度0.748 7;多态信息含量0.701 0,表明3个翘嘴鳜群体在各检测位点中具有较好多态性.对数据进行F-检测,平均Fst值为0.038 3,说明群体间的遗传分化程度低;而群体遗传相似度和遗传距离的计算结果显示:常德和怀化群体的遗传相似度最大,遗传距离最小;而常德与赤壁群体的遗传相似度最小,遗传距离最大.这恰恰与翘嘴鳜群体的流域分布一致.

To protect the germplasm resources of nature Siniperca chuatsi and for genetic breeding, twenty-two polymorphic EST-SSR markers were selected from the EST library, and genetic polymorphic a- nalysis was carried out in three population sampled from Changde, Huaihua and Chibi. The results indi- cated that these twenty-two makers showed abundant polymorphism, 134 alleles were found in all the EST-SSR markers, the allele number per locus ranged from 4 to 8, the mean observed and expected het- erozygosities were 0. 675 4 and 0. 748 7, respectively. And the mean polymorphism information content was O. 701 O. In addition, the genetic index in three populations suggestes better polymorphism in each population. Afer F-test, the mean Fst value was 0. 038 3, which indicates low differentiation was existed in these three populations. The genetic identity of Changde and Huaihua was the highest and the genetic distance was the lowest, while those of Changde and Chibi were reversed, respectively, which is consist- ent with their living regions.