Mutations in metabolic enzymes of the tricarboxylic acid (TCA) cycle, such as succinate dehydrogenase (SDH), fumarate hydratase (FH) and isocitrate dehydrogenase (IDH), lead to cancer, suggesting that altered metabolism could play an active role in tumorigenesis.1 Our laboratory studies how FH loss leads to renal cancer to dissect the link between altered metabolism and cancer. Here, IDH3A is linked to cancer.