Interaction of methylenetetrahydrofolate reductase genotype and smoking habit in Taiwanese lung cancer patients.

UNLABELLED The aim of this study was to evaluate the association and interaction of genotypic polymorphisms in methylenetetrahydrofolate reductase (MTHFR) and environmental factors with lung cancer in Taiwan. Two well-known polymorphic variants of MTHFR, C677T (rs1801133) and A1298C (rs1801131), were analyzed in association with lung cancer susceptibility, and discussed their joint effects with individual habits on lung cancer risk. PATIENTS AND METHODS In total, 358 patients with lung cancer and 716 healthy controls recruited from the China Medical Hospital in central Taiwan were genotyped. RESULTS The MTHFR C677T genotype, but not the A1298C, was differently distributed between the lung cancer and control groups. The T allele of MTHFR C677T was significantly more frequently found in controls than in cancer patients. As for A1298C polymorphism, there was no difference in distribution between the lung cancer and control groups. Gene interactions with smoking were significant for MTHFR C677T polymorphism. The MTHFR C677T CT and TT genotypes in association with smoking conferred a decreased risk of 0.706 (95% confidence interval=0.531-0.939) for lung cancer. CONCLUSION Our results provide the first evidence that the C allele of MTHFR C677T may be associated with the development of lung cancer and may be a novel useful marker for primary prevention and anticancer intervention.