两种凝胶电泳系统对SSR标记多态性的影响

利用 35个SSR引物和 14个玉米自交系直接比较了 3%Metaphor琼脂糖凝胶和 12 %聚丙烯酰胺凝胶电泳对SSR位点多态性水平的影响。结果表明 ,两种凝胶系统检测出的等位基因数目和基因多态性水平存在显著差异 ,12 %聚丙烯酰胺凝胶在区分微小差异片段能力上明显高于 3%Metaphor琼脂糖凝胶。另一方面在两种电泳检测系统下 ,14个自交系之间的遗传相似系数相关性 (r =0 516)达到了极显著水平 (P <0 0 1)。在 10个具有最大多态性信息量的SSR引物中 ,8个在两种凝胶系统中保持相同。利用 8个引物可以对供试自交系进行初步鉴定。笔者认为 ,3%Metaphor琼脂糖凝胶电泳比较适合在遗传作图或基因定位研究中应用 ;而在品种指纹图谱分析或遗传多样性研究中 ,应采用 12 %聚丙烯酰胺凝胶电泳作为检测工具

Comparative Analysis of Polymorphism of SSRs Detected on Two Gel Electrophoresis Systems

Thirty five SSR primers and 14 maize inbred lines were used to comparatively analyze polymorphic level of SSRs on two gel electrophoresis systems.The results showed that the number of alleles and PIC value over 35 SSR primers were significantly different between two gel systems.Polyacrylamide gel(12%) had higher ability than Metaphor agarose gel(3%) in discriminating amplified fragments.On the other hand,the correlation coefficient of genetic similarities between 14 lines obtained on two gel systems was 0 516,significantly correlated at P<0 01 level,indicating that the information explored by two gel systems were relatively similar.Eight SSR primers of 35 primers were identified to have high PIC value and number of alleles over 14 lines on both two gel systems,and could be used for unique DNA fingerprinting of each inbred line tested.Based on the results,3% Metaphor agarose gel was suggested to be used in genetic mapping,while 12% polyacrylamide gel would be used in DNA fingerprinting or genetic variation studies.