PCR-DGGE法检测DNA碱基突变及多态性的方法学评价

Methodological Evaluation on PCR-DGGE Technique in Detecting DNA Mutation and Single Nucleotide Polymorphism

目的了解聚合酶链反应-变性梯度凝胶电泳(polymerase chain reaction-denaturing gradient gelelectrophoresis,PCR-DGGE)法检测DNA碱基突变和分辨单核苷酸多态性(single nucleotide polymorphism,SNP)的能力。方法分别用DNA序列分析法及PCR-DGGE法检测白血病患者治疗前及缓解期的白细胞线粒体DNA D-loop区,以缓解期为对照,了解两种方法检测治疗前白细胞线粒体DNA D-loop区突变的能力并作比较。同时将野生型和突变型DNA以不同比例混合模拟DNA多态性存在,以了解PCR-DGGE检测SNP的灵敏度。结果以DNA序列分析作为对照,PCR-DGGE法检测碱基突变的特异度达到100%,灵敏度为97.1%;PCR-DGGE可检出单碱基突变;PCR-DGGE可检测出约0.5%的多态性存在。结论PCR-DGGE是一个检测DNA碱基突变和多态性存在的较好的方法。

Objective To study the efficiency of polymerase chain reaction-denaturing gradient gel electrophoresis（PCR-DGGE） in detecting the DNA base mutation and single nucleotide polymorphism（SNP）.Methods By DNA sequencing and PCR-DGGE respectively,mutations in the D-loop of the mitochondrial genome were detected in patients with acute leukemia in period of diagnosis and remission,which was regarded as constitutional DNA.The comparison of results was made for evaluating above two methods.Also,the wild type DNA and mutational DNA were mixed at different proportions to mimic the presence of DNA polymorphism.PCR-DGGE was done to study its sensitivity for SNP.Results The specificity and sensitivity of PCR-DGGE in detecting base mutation were 100% and 97.1% respectively.And PCR-DGGE could even detect the presence of polymorphism at rate of 0.5%.Conclusion PCR-DGGE has high sensitivity and specificity and can be applied to detection of DNA mutation and SNP,which is better method for checking DNA mutations.