Table 4

 Frequencies of the methylenetetrahydrofolate reductase (MTHFR) 677C>T and 1298A>C polymorphisms, and odds ratios for colorectal cancer by genotype and genotype combination

OR, odds ratio; CI, 95% confidence interval.
*Adjusted for body mass index, current smoking, recreational and occupational physical activity, and alcohol intake
†Case/referent frequencies: MTHFR 677CC–1298AA, 34/61; 677CT-1298AA, 39/87; 677TT-1298AA, 12/41; 677CC-1298AC, 57/101; 677CT-1298AC, 46/72; 677CC-1298CC, 32/50.
MTHFR 677C>T CC CT TT p Trend
    Cases/referents (total %)123/212 (52.8)85/161 (38.7)12/42 (8.5)
    Unadjusted OR (CI)1.000.90 (0.63–1.27)0.44 (0.21–0.88)0.048
    Adjusted OR† (CI)1.000.91 (0.62–1.30)0.41 (0.19–0.85)0.062
MTHFR 1298A>C AA AC CC p Trend
    Frequency (total %)85/189 (43.3)103/173 (43.7)32/50 (13.0)
    Unadjusted OR (CI)1.001.36 (0.94–1.96)1.52 (0.90–2.57)0.063
    Adjusted OR† (CI)1.001.41 (0.96–2.06)1.62 (0.94–2.81)0.028
Genotype combinations*† 677CC 677CT 677TT
    1298AA, OR (CI)1.000.76 (0.41–1.37)0.46 (0.20–1.04)
    1298AC, OR (CI)1.00 (0.57–1.76)1.20 (0.67–2.15)
    1298CC, OR (CI)1.23 (0.64–2.36)