Table 6.
MTHFR diplotypes and breast cancer survival
| HR (95% CI)1 | p-value | |
| MTHFR diplotypes (n = 198)2 | ||
| CC/AA + CC/AC (high enzyme activity) | 1 | |
| Others (low enzyme activity) | 0.61 (0.3–1.22) | 0.16 |
| ER-negative (n = 84) | ||
| CC/AA + CC/AC | 1 | |
| Others | 0.47 (0.19–1.20) | 0.11 |
| ER-positive (n = 114) | ||
| CC/AA + CC/AC | 1 | |
| Others C | 0.83 (0.27–2.59) | 0.75 |
| African-American (n = 121) | ||
| CC/AA + CC/AC | 1 | |
| Others | 0.22 (0.05–0.96) | 0.04 |
| Caucasian (n = 77) | ||
| CC/AA + CC/AC | 1 | |
| Others | 1.19 (0.36–3.96) | 0.78 |
| No Chemotherapy (n = 81) | ||
| CC/AA + CC/AC | 1 | |
| Others | 0.54 (0.15–1.96) | 0.35 |
| Chemotherapy (n = 117) | ||
| CC/AA + CC/AC | 1 | |
| Others | 0.59 (0.25–1.38) | 0.23 |
1 Cox Proportional-Hazards regression with adjustments for age at diagnosis, race, BMI, estrogen receptor, TNM stage, and chemotherapy. Time at risk and number of events for the strata are shown in Tables 4 and 5.
2 MTHFR diplotypes were generated from the C677T and A1298C genotypes using the information shown in Table 3. Diplotypes were dichotomized into a group that encodes a high activity enzyme [CC(677) and AA or AC(1298)] and a group that encodes a low activity enzyme (all other diplotypes).