The incorporation of H2A.Z into the promoter regions of oestrogen receptor (ERalpha) target genes (for example, TFF1) activates transcription in the presence of oestrogen in breast cancer cells9, and one isoform of H2A.Z mediates proliferation and drug sensitivity in melanoma by interacting with BRD2 and E2F target genes39. Here, ESR1 is linked to breast cancer.