SDHB and renal cell carcinoma: Mutations in protein subunits of succinate dehydrogenase (SDHA/SDHB/SDHC/SDHD and assembly factor SDHAF2) and fumarate hydratase (encoded by the single gene FH) lead to rare forms of renal cell carcinoma (RCC; denoted by SDHRCC and FHRCC, respectively) [1].