Touchdown thermocycling program enables a robust single nucleotide polymorphism typing method based on allele-specific real-time polymerase chain reaction.
Different methods have been developed for single nucleotide polymorphism (SNP) typing during recent years. Allele-specific polymerase chain reaction (ASPCR) is a cost-saving method that scores SNPs by difference of the PCR efficiency of allele-specific primers. However, ASPCR for SNP typing is notoriously confounded for its locus-specific unpredictability and the laborious gel electrophoresis. In the current study, we investigated the real-time kinetics of ASPCR and found that a simple touchdown thermocycling protocol improved its specificity significantly. Combined with real-time PCR, we developed a homogeneous genotyping method and scored more than 1000 genotypes, including all transition and transversion SNPs. A clear genotyping result was identified and validated the robustness of the method. Optimization of reactions and intrinsic modification of allele-specific primers, a laborious process but one that is repeatedly reported to be inevitable for successful ASPCR, was proved to be unnecessary with our method. Accuracy was confirmed with mass spectrometry. These characters enabled real-time ASPCR with the touchdown thermocycling protocol being very competitive among various SNP typing methods for large-scale genetic studies.
Wu
Wei-Ming
WM
Department of Dermatology, Chang Gung Memorial Hospital, Taipei, Taiwan.
Tsai
Hsiang-Ju
HJ
Pang
Jong-Hwei S
JH
Wang
Hsin-Shih
HS
Hong
Hong-Shang
HS
Lee
Yun-Shien
YS
D000483:Alleles; D017931:DNA Primers; D015894:Genome, Human; D005838:Genotype; D006358:Hot Temperature; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods*; D020641:Polymorphism, Single Nucleotide; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D017931:DNA Primers