The characteristics of the study participants are presented in Table 1. Allele and genotype frequencies of MTHFR C677T polymorphism are presented in Table 2. No significant deviations from Hardy-Weinberg equilibrium were noted in either group. We found a statistically significant inverse association between the MTHFR T allele (35.35% for CRC patients and 41.35% for controls) and CRC risk (OR 0.776; 95% CI 0.603-0.997; p = 0.047). Prevalence of the variant allele (677T) within this population did not differ significantly from the prevalences reported in other Caucasian populations (30-35%) [30,31].

      We observed a difference in overall genotype distribution between the CRC patients and controls (CC 42.61%; CT 44.07%; TT 13.32% for CRC patients and CC 35.13%; CT 47.03%; TT 17.84% for controls) even though it did not reach statistical significance (p = 0.064 TT; p = 0.185 CT; CC as reference). The MTHFR 677T allele was not associated with CRC either in a recessive (TT vs. CT + CC) or in a dominant (TT + CT vs. CC) model (OD 0.708; 95% CI 0.442-1.134; p = 0.149 and OD 0.729; 95% CI 0.729; p = 0.085 respectively), although there was a trend for significance towards the dominant model.