BMPR2 mutations have been identified in about 10% to 25% of sporadic IPAH and more than 70% of familial IPAH patients.[3–5] Currently, the most accredited hypothesis is that loss-of-function BMPR2 mutations result in aberrantly increased TGF-β signaling, which is responsible for the pulmonary arterial remodeling.[6] Here, we report a novel frameshift mutation (c.117InsT, p.Y40fsX48) of the BMPR2 gene, identified in a 19-year-old IPAH patient. This evidence concerns the gene TGFB1 and idiopathic pulmonary arterial hypertension.