脊尾白虾(Exopalaemon carinicauda)近交系3个家系33个微卫星座位的遗传分析

摘要

To analyze the genetic effects and inbred degrees of 3 families ofExopalaemon carinicauda inbred line,33 microsatellite loci were selected for genetic analysis.Composition of alleles of each line was analyzed.Number of allele (N),heterozygosity (H),polymorphism information content (PIC),and mean rate of homozygote were calculated.According to gene frequencies of 33 microsatellites,genetic distances between these lines were estimated.In additon,the dendrograms were obtained based on genetic distances.The results indicatedthat 72 alleles were detected at the 33 loci with an average number of allele of 2.758.The estimation of average N,H and PIC of the whole population was 2.758,0.294,0.272,respectively.The average N in three families were 2.258,0.226,0.214,respectively.The average H in three families were 2.469,0.283,0.300,respectively.The average PIC in three families were 2.219,0.268,0.207,respectively.And 7 loci could be used as special gene loci for genetic detection.Cluster analysis showed that Line A and B were gathered first,and then merged with Line H.In conclusion,this study revealed the pattern of genetic variation at 33 microsatellite loci in three inbred families ofE.carinicauda.And the results indicated that inbred families have reached a certain degree of inbreeding.Some loci could be used as special gene loci for genetic detection and identification of independent genetic groups.This study provided important information for genetic analysis and germplasm conservation in E.carinicauda.%本研究以人工控制条件下采用兄妹交配方式建立的脊尾白虾(Exopalaemon carinicauda)近交系为实验材料,利用33个微卫星座位对近交系3个家系进行了遗传检测.统计各家系的等位基因组成,计算等位基因数(N)、杂合度(H)、多态信息含量(PIC)、平均基因纯合率等遗传参数,利用基因频率计算家系间的遗传距离,并进行聚类分析.结果显示,33个微卫星基因座上共检测到72个等位基因,总群体平均N、H、PIC分别为2.758、0.294、0.272;3个家系的平均N、H、PIC分别为2.258、0.226、0.214;2.469、0.283、0.300;2.219、0.268、0.207;可作为3个家系特异标志位点的基因座分别有2个、4个和1个.聚类分析表明,A系和B系先聚为一支,然后与H系聚在一起.研究结果揭示了脊尾白虾3个近交系在33个微卫星基因座上的遗传变异规律,表明近交家系已达到一定的近交程度;发现各家系潜在的标志基因座,各家系均已构成独立遗传群体.