Further, the BAF180-containing SWI–SNF chromatin remodeling complex is critical for HIF1-mediated transcriptional response and BAF180 is mutated in a subset of ccRCC tumors.7, 8, 9, 10, 11, 23 These observations prompted us to test the hypothesis that BAF180 mutation is associated with HIF1A retention in H1H2 ccRCC tumors. The gene discussed is PBRM1; the disease is nonpapillary renal cell carcinoma.