We queried gene expression for twelve known PAH risk genes (ACVRL1, BMPR2, CAV1, EIF2AK4, ENG, KCNK3, KDR, NOTCH1, SMAD4, SMAD9, SOX17, TBX4) and the two new candidate risk genes (FBLN2, PDGFD). The gene discussed is KCNK3; the disease is pulmonary arterial hypertension.