[A new genotyping method, PCR-CTPP].

The polymerase chain reaction with confronting two-pair primers (PCR-CTPP) is an inexpensive genotyping method, which is applicable for most single nucleotide polymorphisms(SNPs). In this method, allele-specific DNA products are amplified by applying appropriately designed two-pair primers (four primers) into a conventional PCR tube, followed by agarose gel electrophoresis. Duplex or triplex PCR-CTPP is also possible in a single tube, which reduces time and costs. An example of multiplex PCR-CTPP is described for NQO1 C609, GSTM1, and GSTT1. This convenient genotyping tool may be useful in health checkup to detect high risk individuals for some diseases, and to prevent such individuals from developing the diseases.