Rapid Detection of the GSTM3 A/B Polymorphism Using Real-time PCR with TaqMan® Probes

Glutathione S-transferases (GSTs) are a group of phase II detoxification enzymes, which catalyze the conjugation of glutathione (GSH) with carcinogens, among other xenobiotics. The GSTM3 gene is part of the GSTs gene family, and its polymorphism A/B has been associated with risk and protective effects of several cancers. This genetic variant is a deletion of 3 bp (AGG) in intron 6. Previous association studies have performed genotyping using techniques such as polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). In this study, we took advantage of the TaqMan® probes features and developed a reliable, faster, more simple and economic method to identify the 3-bp deletion. Our allelic discrimination method was able to distinguish between homozygous A/A, heterozygous A/B and homozygous B/B samples, as shown by TaqMan® based real-time PCR. Results were validated by Sanger Sequencing. In conclusion, we developed a specific and rapid method to detect the 3-bp deletion from the GSTM3 A/B polymorphism.