Associations between BRCA1 DNA methylation and breast cancer have more commonly been reported by studies that specifically examined BRCA1 promoter methylation in younger women (< 45 years) or stratified their findings by age at diagnosis.21,22,64–66 When we specifically sampled for early-onset breast cancer cases (< 40 years), the association with BRCA1 promoter methylation and breast cancer risk is much stronger (OR 3.5, 95% CI: 1.4,10.5).21 Wodjacz et al.67 measured BRCA1 methylation in post-menopausal women and failed to find any significant differences between cases and controls. Here, BRCA1 is linked to breast cancer.