BMPR2 and idiopathic pulmonary arterial hypertension: Idiopathic pulmonary arterial hypertension (IPAH), one of 6 subcategories proposed by Dana Point Classification [1], accounts for approximately half of PAH cases [2] and up to 40% of patients with no family history carries mutations in the bone morphogenetic protein receptor type 2 (BMPR2) gene [1].