While specific patterns of copy number alteration were not observed in the CIMP-RCC or the type 2 PRCC, both demonstrated an increased loss of chromosome 22 that encodes NF2 from the HIPPO pathway and SMARCB1, a fundamental component of the SWI/SNF complex, and the CIMP-RCC had loss of chromosome 13q at a similar rate to ChRCC (60% versus 61.3%) that encodes RB1 and BRCA2 (Figure 1B). This evidence concerns the gene RB1 and chromophobe renal cell carcinoma.