Allele-specific PCR with a novel data processing method based on difference value for single nucleotide polymorphism genotyping of ALDH2 gene

Single nucleotide polymorphism (SNP) analysis based on allele-specific polymerase chain reaction (AS-PCR) is a relatively effective and economical method compared with other genotyping technologies such as DNA sequencing, DNA hybridization and isothermal amplification strategies. But AS-PCR is limited by its labor-intensive optimization of reaction parameters and time-consuming result assessment. In this study, we put forward a novel idea of data processing to address this problem. SNP analysis was accomplished by AS-PCR with endpoint electrochemical detection. For each sample, two separate reactions were run simultaneously with two sets of allele-specific primers (wild-type primers for W system and mutant primers for M system). We measured their redox current signals on screen-printed electrodes once AS-PCR finished and calculated the difference value of current signals between two systems to determine the genotyping result. Based on the difference value of fluorescent signals, real-time fluorescent PCR was used to study reaction parameters in AS-PCR. With screened parameters, we obtained the genotyping results within 50 min. 36 hair-root samples from volunteers were analyzed by our method and their genotypes of ALDH2 gene (encoding aldehyde dehydrogenase 2) were totally identical with data from commercialized sequencing. Our work first employed difference value between two reaction systems to differentiate allele and provided a novel idea of data processing in AS-PCR method. It is able to promote the quick analysis of SNP in the fields of health monitor, disease precaution, and personalized diagnosis and treatment.