Succinate dehydrogenase (SDH) is a highly conserved protein complex located on the inner mitochondrial membrane where it functions during the Krebs cycle by oxidizing succinate to fumarate (1). This reaction is also important for feeding electrons into the electron transport chain. SDH complex contains four subunits: SDH-A, -B, -C, and -D. Mutation of SDH-A often leads to mitochondrial encephalopathy while mutations to subunits B, C, and D lead to tumors of the head and neck (1).
