作　　者： ; ; ; ; ; ; ;

机构地区： 中国水产科学研究院珠江水产研究所

出　　处： 《水生生物学报》 2009年第3期498-508,共11页

摘　　要： 应用筛选到的19对微卫星引物,对四个不同来源的奥利亚罗非鱼(Oreochromis aureus)群体(奥利亚罗非鱼83系、奥利亚罗非鱼02系、奥利亚罗非鱼05系和红色奥利亚罗非鱼)的基因组DNA进行PCR扩增,分析其群体遗传结构和亲缘关系。根据几个群体在19个位点上的PCR扩增图谱,统计计算各群体的遗传多样性指数。四个群体的平均观测遗传杂合度值在0.154—0.391间;平均预期杂合度在0.181-0.428间;平均多态信息含量值在0.1513—0.3882间,说明它们的遗传多样性水平较低。遗传偏离指数D的评估结果显示这4个群体有多个位点存在不同程度的Hardy-Weinberg遗传平衡偏离。运用MicroChecker软件进行零等位基因预测,结果显示除红色奥利亚罗非鱼群体外,其他3个群体中均可能存在零等位基因位点。各群体零等位基因的位点数分别为:83系1个,02系3个,05系7个,红奥群体为0。零等位基因位点的存在可能是导致位点发生Hardy-Weinberg遗传平衡偏离的原因之一。4个群体中,05系群体与83系群体间的遗传相似性系数最高(0.9422),遗传距离最小(0.0596),说明两者亲缘关系最近;83系群体与红奥群体的遗传相似性系数最低(0.6977),遗传距离最大(0.3599),可推断两者亲缘关系最远。根据群体间的遗传距离采用UPGMA法进行聚类,结果表明:83系首先与05系聚类为一支,然后与02系群体聚类,最后与红奥群体聚类。聚类结果说明红奥群体与其他三个群体亲缘关系最远;83系群体与05系群体亲缘关系最近,与02系群体次之。 Genetic diversity and phylogenetic relationships among four breed varieties of Oreochromis aureus （83） , O. aureus （02）, O. aureus （05） and red O. aureus were studied using microsatellite analysis technology. 19 pairs of microsatellite DNA primers of Oreochromis niloticu registered in GenBank which were selected and proved to amplify successfully on Oreochromis aureus by pre-experiment were used. The PCR reaction condition especially concentration of Mg^2＋ and annealing temperature were adjusted for each pair of primers. Amplified PCR products were electrophoresed in PAGE and stained according to the silver stain procedures and then imagined by Alphalmager. A total of 82 alleles were obtained from the four populations. The number of alleles for each locus ranged from 2-8, and the average alleles was 4.3 each locus. Average observed heterozygosity and average expected heterozygosity were calculated by POPGENE3.2 software. The results showed that the observed value of average heterozygosity of the four O. aureus populations ranged from 0. 154 to 0. 391. The expected value of average heterozygosity ranged from 0. 181 to 0. 428, and the average polymorphism information contents ranged from 0. 1513 to 0. 3882, respectively. The lowest genetic diversity level was found in the O. aureus （02）. The highest genetic similarity index （0. 9422） and the lowest genetic distance （0. 0596 ） were found between O. aureus （05） and O. aureus （83） , which indicated a closer phylogenetic relationship between these two populations. On the other hand, the lowest genetic similarity index （0. 6977） and the highest genetic distance （0. 3599） existed between O. aureus （ 83 ） and red O. aureus, which suggested a farthest phylogenetic relationship between these two populations. The evaluation results of the genetic deviation index D revealed that there were loci departed from Hardy-Weinberg equilibrium in all the four O. aureus populations. Results of null allele anal- ysis by MicroChecker showed

关 键 词： 奥利亚罗非鱼 微卫星 群体遗传多样性 遗传距离 遗传平衡

领　　域： [生物学]