Sirtuin 3, a mitochondrial protein among others involved in mtDNA repair via 8-Oxoguanine glycosylase 1 [305] is downregulated in PAH patients and monocrotaline-induced PH rat whereas Sirtuin 3 knockout mice spontaneously develop PAH [306]. The gene discussed is SIRT3; the disease is pulmonary arterial hypertension.