To give several examples, inactivation of 3-hydroxybutyrate dehydrogenase type 2 (bdh2) leads to mitochondrial dysfunction and mitophagy, which delays erythroid maturation in zebrafish15, cytosolic p53-mediated inhibition of mitophagy leads to heart failure in mice16, while in Drosophila, knockdown of optic atrophy 1 (opa1) results in smaller mitochondria, developmental defects, and muscle degeneration17. The gene discussed is BDH2; the disease is heart failure.