Table 3 Age-adjusted Odds ratios (ORs) and 95% confidence intervals (CIs) for the association between age at first birth and breast cancer as defined by gene-specific promoter methylation (comparing parous case women with and without methylated breast cancer [N = 736]), Long Island Breast Cancer Study Project
|  | ≤23 years | 23–27 years of age | ≥27 years | ||||||
|---|---|---|---|---|---|---|---|---|---|
Gene promoter | Methylated/ Unmethylated | OR | 95% CI | Methylated/ Unmethylated | OR | 95% CI | Methylated/ Unmethylated | OR | 95% CI |
APC | 105/120 | 1.00 | reference | 108/122 | 1.08 | 0.90–1.30 | 118/115 | 1.18 | 0.81–1.70 |
BRCA1 | 130/110 | 1.00 | reference | 135/106 | 1.28 | 1.07–1.53 | 166/86 | 1.63 | 1.14–2.35 |
CDH1 | 20/209 | 1.00 | reference | 9/199 | 0.66 | 0.44–1.00 | 10/220 | 0.44 | 0.20–0.99 |
CCND2 | 45/184 | 1.00 | reference | 44/164 | 1.00 | 0.79–1.26 | 46/184 | 1.00 | 0.63–1.59 |
DAPK | 38/191 | 1.00 | reference | 32/176 | 0.78 | 0.60–1.02 | 25/205 | 0.61 | 0.36–1.04 |
ESR1 | 108/130 | 1.00 | reference | 117/122 | 0.94 | 0.79–1.12 | 105/143 | 0.88 | 0.62–1.26 |
GSTP1 | 67/162 | 1.00 | reference | 59/149 | 0.90 | 0.74–1.11 | 58/172 | 0.82 | 0.54–1.23 |
HIN | 150/79 | 1.00 | reference | 129/79 | 0.87 | 0.72–1.05 | 135/95 | 0.75 | 0.51–1.09 |
P16 | 13/205 | 1.00 | reference | 7/216 | 0.69 | 0.42–1.11 | 7/219 | 0.47 | 0.18–1.24 |
PGR | 27/213 | 1.00 | reference | 25/216 | 1.14 | 0.86–1.49 | 35/217 | 1.29 | 0.75–2.23 |
RARB | 59/170 | 1.00 | reference | 58/150 | 1.08 | 0.88–1.32 | 66/164 | 1.16 | 0.77–1.75 |
RASSF1A | 188/41 | 1.00 | reference | 178/30 | 1.21 | 0.94–1.56 | 200/30 | 1.46 | 0.88–2.44 |
TWIST1 | 44/185 | 1.00 | reference | 30/178 | 0.69 | 0.53–0.91 | 24/206 | 0.48 | 0.28–0.82 |