Table 2.

Breast cancer ORs (95% CIs) for the MTHFR C677T and A1298C polymorphisms

GenotypeBivariate*
Multivariate
Premenopausal*,
Postmenopausal*,‡
n§OR (95% CI)nOR (95% CI)nOR (95% CI)nOR (95% CI)
677
    CC573/12111.00534/11481.0070/1861.00429/8491.00
    CT479/9200.98 (0.83-1.15)441/8660.97 (0.82-1.14)51/1461.01 (0.64-1.59)365/6480.96 (0.80-1.16)
    TT137/2830.86 (0.67-1.09)131/2710.85 (0.66-1.09)18/401.27 (0.65-2.47)103/2070.80 (0.60-1.06)
    P0.280.250.570.16
1298
    AA741/14931.00685/14051.0078/2361.00562/10481.00
    AC371/8010.92 (0.79-1.08)349/7640.92 (0.78-1.08)51/1191.36 (0.89-2.07)274/5680.88 (0.73-1.06)
    CC77/1201.20 (0.88-1.65)72/1161.18 (0.85-1.62)10/171.96 (0.84-4.55)61/881.18 (0.83-1.69)
    P0.930.960.060.78
  • NOTE: aP value for a gene dosage term assigned 1, 2, and 3 for 0, 1, and 2 variant alleles, respectively.

  • * Adjusted for age at blood draw and race and/or ethnicity.

  • Further adjusted for age at menarche, age at first birth, parity, and body mass index (83 cases and 129 controls were excluded due to missing covariates).

  • Premenopausal status was defined as still menstruating at baseline. Postmenopausal status was defined as menstruation stopping and natural menopause, bilateral oopherectomy, or age >55 years at cohort entry. Women with a simple hysterectomy with age ≤55 years or who could not be classified into these groups were excluded (153 cases and 338 controls).

  • § No. cases/no. controls.

  • P value for a gene dosage term assigned 1, 2, and 3 for 0, 1, and 2 variant alleles, respectively.