KCNK3 and pulmonary arterial hypertension: <b>Background</b>: Pulmonary arterial hypertension is a rare but life-threatening condition in children, with hereditary forms often being linked to mutations in genes such as bone morphogenetic protein receptor type 2 (<i>BMPR2</i>), caveolin 1 (<i>CAV1</i>), and potassium channel subfamily K member 3 (<i>KCNK3</i>).