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.

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)	1.00	0.90 (0.63–1.27)	0.44 (0.21–0.88)	0.048
Adjusted OR† (CI)	1.00	0.91 (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)	1.00	1.36 (0.94–1.96)	1.52 (0.90–2.57)	0.063
Adjusted OR† (CI)	1.00	1.41 (0.96–2.06)	1.62 (0.94–2.81)	0.028
Genotype combinations*†	677CC	677CT	677TT
1298AA, OR (CI)	1.00	0.76 (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)	–	–

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.