SMAD9 and pulmonary arterial hypertension: An NGS panel was analysed, including 19 PAH-associated genes (ABCA3, ACVRL1, BMPR1B, BMPR2, CAV1, EIF2AK4, ENG, FOXF1, GDF2, KCNA5, KCNK3, NOTCH1, NOTCH3, RASA1, SMAD1, SMAD4, SMAD9, TBX4, and TOPBP1) as previously described [6].