我国新引进吉富品系尼罗罗非鱼群体的遗传多样性分析

Genetic Diversity Analysis in A Newly Introduced Population of GIFT Strain Nile Tilapia (Oreochromis niloticus)

选取罗非鱼(Oreochromis spp.)第二代遗传连锁图谱中的26个微卫星位点,对淡水渔业研究中心引进的、由60个家系组成的吉富品系尼罗罗非鱼(O.niloticus)群体进行遗传结构分析。结果显示,26个微卫星位点在吉富罗非鱼群体中共检测到124个等位基因,各位点的等位基因数为3～7个,平均4.8个。片段长度104～322 bp,平均杂合度观测值为0.622 1,平均杂合度期望值为0.642 3,平均多态信息含量(PIC)为0.633 4。所检测的26个位点中,有25个位点属于高度多态位点(PIC>0.5),占所检测位点的96.15%;1个位点属于中度多态位点。结果表明,该吉富罗非鱼群体多态信息含量丰富,遗传多样性水平较高。因而该群体仍然具有较大的选育潜力,可以作为选育的基础群体开展进一步的选育工作。

In this study,26 microsatellite loci from the second-generation genetic linkage map of tilapia（Oreochromis spp.） were used to analyze the genetic structure of the GIFT strain Nile tilapia（O.niloticus） consisting of 60 families introduced by Freshwater Fisheries Research Center.A total of 124 alleles were detected in the population by 26 microsatellite primers,and the number of allele at each locus ranged from 3 to 7,with an average of 4.8.The average observed heterozygosity was 0.622 1 while the average expected heterozygosity was 0.642 3.The average polymorphism information content（PIC） was 0.633 4.Out of 26 detected loci,25 loci were in a high polymorphism degree（PIC 0.5）,while the remaining 1 locus was in a medium polymorphism degree.The results indicate rich polymorphism information content and large geneticdiversity in the population.This introduced GIFT strain Nile tilapia population has a large selection potential and may be used as a base population for further selection.