吉富罗非鱼雌雄群体遗传差异的SSR分析

为探讨吉富罗非鱼(genetic improvement of farmed tilapia,GIFT)雌、雄群体间的遗传差异,本研究对国家级广西南宁罗非鱼良种场雌、雄吉富罗非鱼进行了遗传差异分析。研究结果表明,选取的11对SSR引物中有10对能获得稳定的目的条带;每个SSR基因座的等位基因数在2～4个之间,雌性罗非鱼的平均等位基因(Na)2.9个,稍高于雄性的2.8个;雌、雄吉富罗非鱼平均观察杂合度(HO)分别为0.4183和0.4154,多态信息含量(PIC)分别为0.4048和0.3932,属中度多态;雌雄个体间的遗传距离和相似性指数分别为0.0908和0.9132。此外,SSR基因座PRL-SO2在雄鱼中偏离Hardy Weinberg平衡(P0.005)。上述结果表明,吉富罗非鱼雌、雄群体的SSR多态性基本相同,推测这两者基因组间的差异较小。

Genetic Diversity between Sexes of Genetic Improvement of Farmed Tilapia Reveal by SSR Analysis

In this research, we have comparatively analyzed the genetic diversity of Genetic Improvement of Farmed Tilapia (GIFT) in Nanning, Guangxi tilapia farm-level seed, in order to obtain genetic informations of female and male GIFT. The results showed that there were 10 SSR primers successfully amplified with stable target bands within 11 tested SSR primers to identify the polymorphism for the tested GIFT. The number of alleles ranged was 2～4 in each SSR locus, and the average alleles in female GIFT was 2.9 slightly higher than that of 2.8 in male GIFT. Then the average of polymorphism information content (PIC), observed heterozygosity(H_o) in female and male GIFT was 0.404 8 and 0.393 2, 0.418 3 and 0.415 4 respectively, so it revealed the midrange polymorphism of fe-male and male GIFT. Genetic similarity index and genetic distance between individual of female and male GIFT was 0.090 8 and 0.913 2 respectively. We also found that SSR locus PRL-SO_2 showed significant departure from Hardy-Weinberg equilibrium after sequential bonferroni correction (P< 0.005) in male GIFT. Above-mentioned results indicated that SSR locus diversity was the same between male and female GIFT, and it was also presumed that genome variance between male and female GIFT should be the same.