Pathogenic BMPR2 mutations result in BMPR2haploinsufficiency with a decrease in pulmonary vascular BMPR2 proteinexpression; notably, BMPR2 expression is also decreased in the pulmonaryvasculature of patients with other forms of pulmonary hypertension, suggestingmechanistic parallels between the various subgroups [34]. The gene discussed is BMPR2; the disease is pulmonary hypertension.