FH and mitochondrial disease: Indeed, many of the symptoms of ACO2 deficiency are common to mitochondrial disease and other TCA cycle enzymopathies, including deficiency of α‐ketoglutarate dehydrogenase (EC 1.2.4.2; Odièvre et al., 2005), succinate dehydrogenase (EC 1.3.5.1; Bourgeron et al., 1995), fumarate hydratase (EC 4.2.1.2; Bourgeron et al., 1994) and succinate‐coenzyme A ligase (EC 6.2.1.5; Elpeleg et al., 2005; Ostergaard et al., 2007).