After adjusting other potential confounding variables such as age, gender, folate intake, we found that the IGF-2 gene hypomethylation frequency in the transitional cell carcinoma tissues from carriers of MTHFR variant CT and TT genotypes was significantly increased compared with the MTHFR wildtype genotype CC, with the OR values of 4.33 (95% CI=1.06-10.59) and 4.95 (95% CI=1.18-12.74), respectively (Figs. 2,3 and Table 3). This evidence concerns the gene MTHFR and transitional cell carcinoma.