Furthermore, the distribution of CpG β-values for the single most influential covariate in the CBX2 model, a CpG site located within the second intron of the CBX2 gene (Supplementary Figure 6), showed a clear reduction in DNA methylation (P-value < 1 × 10−8, Wilcoxon rank-sum test) in breast tumours that overexpress CBX2 (Fig. 1b). This evidence concerns the gene CBX2 and breast neoplasm.