微卫星分子标记对德国镜鲤两家系遗传多样性的比较分析

Microsatellite marker analysis on genetic diversity in two German mirror carp(Cyprinus carpio L.) families

利用35个微卫星分子标记对黑龙江松浦实验站2个家系德国镜鲤的观测杂合度（Ho）、期望杂合度（He）、多态信息含量（PIC）和有效等位基因数（Ae）等进行遗传检测，根据基因频率计算遗传相似系数和Nei氏标准遗传距离，x^2检验估计Hardy—Weinberg平衡，并与其亲本的各项遗传指标进行比较。2个家系共检测到108个等位基因，平均每个基因座扩增得到3．0857个等位基因，片段长度在136～383 bp之间。结果显示，2个家系的多态性指标均适中，多态信息含量分别为0．4376、0．3254，多态性扩增的基因座的有效等位基因数在1．0339～4．6997个不等，平均有效等位基因数依次为2，2706、1．8432，无偏期望杂合度在0．1831～0．8006之间，平均值分别为0，5123、0．3881。但连锁不平衡分析表明，这2个家系在较大的选择压力下，已偏离Hardy—Weinberg平衡，讨论了出现这种现象的可能原因。

Thirty five microsatellite loci were used for analyzing two families of mirror carp （Cyprinus carpio L. ）,namely,SX,YX. Observed （Ho） and expected （He） heterozygosity values, polymorphic information content （PIC） and number of effective alleles （Ae） were all calculated, the Hardy-Weinberg Equilibrium was checked according to the test of x^2 , and genetic indices with their parents were compared. Totally 108 alleles were procured. The lengths are between 136 bp and 383 bp. The number of alleles in each locus is 3. 085 7 on an average. The result shows that the level of genetic variability is moderate in two families. Polymorphic information contents （PIC） of the two mirror carp families are 0. 437 6 and 0. 325 4, respectively. Effective alleles （Ae） are from 1. 033 9 to 4. 699 7, number on average in each family are 2. 270 6 and 1. 843 2. The average expected heterozygosity values （He） are 0. 512 3 and 0. 388 1, respectively. The analysis of linkage disequilibrium indicated that the two families have deviated from Hardy-Weinberg Equilibrium, and the cause of this kind of deviation phenomenon was discussed.