五个斑点叉尾群体的微卫星遗传多样性分析

Genetic diversity based on microsatellite markers in five channel catfish(Ictalurus punctatus) populations

用8对微卫星引物对1997-2004年引进的5个斑点叉尾群体进行遗传多样性分析,计算并统计等位基因数、多态信息含量(PIC)、杂合度、遗传相似性系数、遗传距离等参数。实验显示8个微卫星位点在5个斑点叉尾群体中共检测到42个等位基因,平均期望杂合度为0.6338～0.7320,表明其遗传多样性程度处于中等偏上水平。平均多态信息含量为0.5756～0.6869,说明基因座为高度多态基因座(PIC>0.5)。群体间遗传相似系数为0.7504～0.9203。聚类分析显示,04群体与其他4个群体的亲缘关系较远。结果表明:引进的5个斑点叉尾群体均具有较高的遗传多样性,遗传信息丰富,遗传变异大,为良好的育种材料。

To provide background on the genetics of cultured channel catfish（Ictalurus punctatus）and basic information for breeding,we surveyed five channel catfish populations using 8 microsatellite loci to estimate the genetic variation.A total of 42 alleles were detected.Mean expected heterozygosity（He）ranged between 0.6338 and 0.7320,and mean polymorphism information content（PIC）ranged between 0.5756 and 0.6869,which were high polymorphism（PIC0.5）,the genetic similarity coefficient was from 0.7504 to 0.9203,the cluster analysis by UPGMA using the MEGA software package（version 4.0）indicated high similarity among all populations except population 04,indicating that these five channel catfish populations were highly polymorphic,abundant in genetics information and had a great potential of selective breeding.