AQP1 and pulmonary arterial hypertension: Mutations in CAV1, which encodes caveolin‐1 [17], KCNK3 (potassium channel subfamily K member 3) [18], TBX4 (T‐box 4) [19,20], ATP13A3 (ATPase 13A3), AQP1 (aquaporin 1), SOX17 (SRY‐box 17), and GDF2 (growth differentiation factor 2/BMP9) [21] have been also discovered in PAH.