For those who had folate intake<450 ug/day, MTHFR 667TT genotype was associated with a higher risk of breast cancer (OR=2.45, 95% CI=1.09-5.82, P=0.02), and statistically significant association disappeared among individuals with folate intake≥500 mg/day. The gene discussed is MTHFR; the disease is breast carcinoma.