二核苷酸微卫星PCR扩增的影子带及其来源  

Shadow Bands in PCR Amplification of Dinucleotide Microsatellites and Their Origin

作　　者：王吉振[1] 王爱国[1] 储明星[2] 李宁[3] 傅金恋[1] 易建红 高福才 

机构地区：[1]中国农业大学动物科技学院,北京100094 [2]中国农业科学院北京畜牧兽医研究所,北京100094 [3]中国农业大学农业生物技术国家重点实验室,北京100094 [4]河北省任丘市畜牧水产局,任丘062550

出　　处：《畜牧兽医学报》2007年第3期241-246,共6页ACTA VETERINARIA ET ZOOTECHNICA SINICA

基　　金：国家自然科学基金资助项目(30300248;30140004和39770541)

摘　　要：2个绵羊二核苷酸微卫星BM143和BMS2508的PCR扩增产物在非变性(中性)聚丙烯酰胺凝胶电泳(nPAGE)中形成滞后于主带的影子带。影子带比主带小2 bp。实际上主带由两部分组成:表明微卫星正确大小的PCR特异扩增的高浓度条带(特异扩增带)和比特异扩增带小2 bp的PCR非特异扩增的低浓度条带(非特异扩增带)。本试验初步证明影子带是微卫星的一条特异扩增带和一条非特异扩增带错配形成的异源双链。本研究结果表明,影子带的出现并不改变特异扩增带在nPAGE中的正常迁移率。The PCR products of two ovine dinucleotide microsatellites BM143 and BMS2508 were separated on nondenaturing polyacrylamide gel electrophoresis （nPAGE）. Shadow bands were seen 2 bp below the main bands. Actually the main band was composed of two components： specifically a PCR-amplified high-density band that indicates the correct size of the microsatellite （specific band） and nonspecifically a PCR-amplified low-density band that is 2 bp shorter than the specific band （nonspecific band）. The results of this study preliminarily demonstrated that the shadow band was heteroduplex DNA formed by a specific band and a nonspecific band. Appearance of shadow bands did not change the normal mobility of specific bands on nPAGE.

关 键 词：二核苷酸微卫星 聚合酶链式反应 影子带 非特异扩增带 特异扩增带 异源双链 

分 类 号：Q75[生物学—分子生物学]