The application of microsatellite markers for parentage determination has been approved in aquaculture which not only can maintain the parentage information,but also greatly reduce the cost in space and man-power and greatly improve breeding selection effect in communal environment,especially in the process of selective breeding.In this study,two selected cross-breeding families (the 49 full-sib families:7 of Cyprinus carpio var.mirror ♀ ×7 ofC.carpio var.wuyuanensis ♂ and the 24 full-sib families:3 ofC.carpio var.wuyuanensis ♀ ×8 of C.carpio var.mirror ♂ ) were evaluated for genetic diversity and inheritance characteristics by 21 microsatellites loci,and examined several properties of microsatellites which could be considered to affect the accuracy of loci in parentage assignment.Finally,13 suitability loci were obtained for parentage assignment,and performance of them showed that:(1) These 13 screened loci were high polymorphic.Mean number of alleles (K),mean expected heterozygosity (He),mean observed heterozygosity (Ho) and mean polymorphic information content (PIC) were respectively 0.505,0.648,0.791 and 0.5889 in the 49 full-sib families and 0.548,0.670,0.819 and 0.6138 in the 24 full-sib families.(2) 13 screened loci were of high discriminatory power.The combined exclusion probability (CPE) was 0.999997978 in the 49 full-sib families and 0.999999583 in the 24 full-sib families.(3) High efficiency of the loci subset was obtained.The CPE of 4 core microsatellite loci (MFW29,HLJ392,HLJ044 and HLJ855) could be accurate to more than 99％ in the two cross-breeding groups.(4) Combined non-exclusion probabilities when the first parent was available (NE-1P),the second parent was available (NE-2P) and parent pairs were available (NE-PP) were respectively 1.34E-02,3.91E-04 and 2.02E-06 in the 49 full-sib families,and were respectively 1.34E-02,3.91E-04 and 2.02E-06 in the 24 full-sib families.(5) The simulations with 99％ confidence indicated that 100％ offspring of 49 full-sib families could be assigned to a parent pair using the 11 most polymorphic loci or more loci,99％offspring of 24 full-sib families could be assigned to a parent pair using the best 9 or more loci.(6) The distance-based method of cluster analysis showed that:the set of 13 loci could clearly distinguished between the offspring of cross-breeding and the unrelated family in the polyculture.Based on these results,a suitable microsatellite-based tool for parentage assignment in cross-breeding carp is obtained,and displays a reliability and high efficacy alternative to physical tagging in subsequently selecting program.%微卫星的亲子鉴定技术既能减少分池饲养带来的遗传性状的差异又能减少其所占用饲养池的数量和管理强度,在水产养殖和品种选育中得到了广泛的应用.本研究应用21对微卫星标记对鲤(Cyprinus carpio)杂交家系(49-同胞家系:德国镜鲤(C.carpio var.mirror)♀×荷包红鲤(C.carpio var.wuynaensis)♂；24-同胞家系:荷包红鲤♀×德国镜鲤♂)进行遗传多样性及遗传特性的评价,并检测影响微卫星标记鉴定准确性的几个特性.研究结果标明,(1)筛选出的13对标记:在49-同胞家系中,平均有效等位基因数(K)、期望杂合度(He)、观测杂合度(Ho)和多态信息含量(PIC)分别为0.505、0.648、0.791和0.5889;在24-同胞家系中,K、He、Ho和PIC分别为0.548、0.670、0.819和0.6138.(2)筛选出的13对标记:在49-同胞家系和24-同胞家系中的联合排除率(CPE)分别达到0.999997978和0.999999583.(3)在两个杂交家系中,4个核心位点(MFW29,HLJ392,HLJ044,HLJ855)的联合排除率均高于99％.(4)三种情况下(一个亲本已知,NE-1P;另一个亲本已知,NE-2P;双亲都己知,NE-PP;)的联合非父排除率在49全胞家系中分别为1.34E-02、3.91E-04和2.02E-06;在24全胞家系中分别为1.34E-02、3.91E-04和2.02E-06.(5)模拟分析显示(置信度为99％),当使用11个或更多标记时,在49全胞家系中亲本与子代的配对率为100％;当使用9个或更多标记时,在24全胞家系中亲本与子代的配对率大于98％.(6) UPGMA聚类图表明:在混养条件下,筛选出的13对标记可以明显地将子代与无亲缘关系的家系区分开.本研究筛选出13对微卫星标记完全适用于荷包红鲤与德国镜鲤杂交家系的鉴定,为品种选育提供有效的鉴定工具.
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