As age played a crucial role in DNA methylation (Horvath, 2013; Nejman et al., 2014), we calculated the correlation between age and methylation levels in controls and BC cases in Study I. All the nine methylation sites of S100P showed significant correlation with age in the controls (Spearmen rhos range from 0.15 to 0.24, p-values range from 9.00E-6 to 0.006; Supplementary Table 3), whereas seven methylation sites of S100P showed significant correlation with age in BC cases (Spearmen rhos range from 0.13 to 0.38, p-values range from 7.3E-11 to 0.025; Supplementary Table 3). The gene discussed is S100P; the disease is breast cancer.