BMPR2 and chronic thromboembolic pulmonary hypertension: One typical example of common genes is bone morphogenetic protein receptor type 2 (BMPR2), which was first revealed in patients with hereditary PAH and patients with IPAH (5–7), and then validated in the development of group 3 PH (8), chronic thromboembolic pulmonary hypertension (8, 9), valvular heart disease complicated with pulmonary artery hypertension (10), and hypoxia-induced animal model (11, 12).