Mice with homozygous deletion of Notch3 do not develop pulmonary hypertension (PH) in response to hypoxic stimulation7 and PH can be successfully treated in rats by administration of a monoclonal antibody that specifically inhibits JAG-1 ligand binding to the NOTCH3 receptor, inhibiting downstream signaling10. This evidence concerns the gene NOTCH3 and pulmonary arterial hypertension.