In a recent study, using IHC or RNA sequencing on a cohort of 497 breast cancers, Puppe et al. showed that EZH2 is expressed at significantly higher levels in BRCA1-deficient breast cancers, classified through BRCA1 mutation status, BRCA1-promoter hypermethylation, or a BRCA1-like DNA copy number profile. This evidence concerns the gene BRCA1 and breast carcinoma.