FOXA1 is a TF that is mutated or amplified less frequently in human breast cancers (~ 2% mutated and ~ 1% amplified; Cancer Genome Atlas Network, 2012; Robinson et al,2013) and usually found to be altered in ER+ tumors (Fig 5; Nik‐Zainal et al,2016). The gene discussed is ESR1; the disease is breast carcinoma.