微卫星标记应用于凡纳滨对虾家系鉴别的研究

The Application of Microsatellite Markers for Parentage Determination in Selective Breeding of Pacific white Shrimp (Litopenaeus vannamei)

以人工选育建立的凡纳滨对虾(Litopenaeusvannamei)全同胞家系为实验材料,探讨了微卫星标记对混养家系进行亲权鉴定的可能性。Cervus模拟分析表明从10个微卫星基因座组合中选取的多态性信息含量最高的6个进行组合与原组合的累积排除概率均在0.99,多态性信息含量最高的6个基因座的组合判定正确率为0.97,置信度为95%。在家系混养的模拟实验中使用这6个高多态性的微卫星基因座从20个候选雌虾中找到真正母亲的概率为88%,从30个候选雄虾中找到真正父亲的概率为78%,低于理论预测值,分析可能与微卫星基因座中的无效等位基因、等位基因的突变以及PCR过程中Taq酶发生链滑移等因素有关。

Used simulations and controlled mating to examine the potential of microsatellite markers in assigning parentage to Pacific white shrimp progeny. Cervus simulations demonstrated that the theoretical expectations for parentage exclusion of 10 microsatellite loci and six most polymorphic of the 10 loci were both 0.99, and the assignment success rate of the 6 most polymorphic microsatellite loci set was nearly to 0.97 with 95% confidence. Based on this information, offspring from 10 crosses where parents were known were genotyped by the 6 microsatellite loci and used for par- entage analysis. The result showed that assignment success of the progeny to their ＇true＇mother and father was 88% and 78% respectively, which were lower than predicted by the Cervus simulations. This could be explained by the existence of null or mutant alleles and by Taq DNA Polymerase slippage in the microsatellite loci.