BMPR2 mutations are the most common genetic cause of pulmonary arterial hypertension (PAH). Pulmonary artery endothelial cells (PAECs) with reduced BMPR2 expression are linked to a persistent DNA damage after reoxygenation. Forkhead box F1 (FOXF1) is a transcription factor with affinity for endothelial cells in the lung, and its reduced expression has also been associated with DNA damage in those cells and PAH.