We also compared the levels of FOXA1 methylation in different familial breast tumours and found that FOXA1 methylation levels were significantly higher in BRCA1-mutated tumours compared with BRCA2, BRCAx (non-BRCA1/2) and BRCA2/x tumours (P=0.006, P=0.046 and P=0.006, respectively; Student's t-tests; Figures 10d and e, Supplementary Figures S9 and S10). Here, BRCA1 is linked to breast neoplasm.