Currently approved PAH-specific therapies target four different pathways: (1) the endothelin pathway promotes vasoconstriction and proliferation, therefore endothelin receptor blockers (ERA) are used, (2) prostacyclins or prostanoid receptor agonists directly promote vasodilatation and partially exert anti-proliferative effects, (3) activation of the NO-sGC-cGMP pathway has vasodilatory and anti-proliferative effects, and (4) in the subset of vasoresponsive PAH patients voltage-dependent calcium-channel blocker are used (196, 197). The gene discussed is SGCB; the disease is pulmonary arterial hypertension.