THE METHYLENETETRAHYDROFOLATE REDUCTASE 677C -> T POLYMORPHISM AND LUNG CANCER RISK IN A CHINESE POPULATION

Background: We examined the relationship of the MTHFR C677T genotype with the risk of lung cancer in a nested case- control study conducted in a cancer screening follow-up study in Taiwan. Materials and Methods: A total of 59 histologically confirmed lung cancer cases and 232 cancer- free controls were recruited between July 1990 and December 2000. The MTHFR C677T genotype was determined by a PCR- restriction fragment length polymorphism assay. Results: The MTHFR 677T variant genotype, including 677CT and 677TT, was observed in 39% of cases and 47% of controls. The resultant adjusted odds ratio (OR) was 0.71 (95% confidence interval[ CI] = 0.39-1.30). The inverse association of the MTHFR 677T variant genotype with lung cancer risk was apparent in both smokers and nonsmokers. Conclusion: These results suggest that the MTHFR 677T variant genotype reduces the risk of lung cancer. Larger studies incorporating dietary folate intake and the variant genotypes are needed to clarify our results