For example, approximately 8,000 people with cystic fibrosis61, 252,000 people with Stargardt disease62, 31,000 people with phenylketonuria63 and 43,500 people with Duchenne muscular dystrophy64 have nonsense mutations in CFTR, ABCA4, PAH or DMD, respectively, that could in principle be treated with common PERT prime editing agents after further optimization. Here, CFTR is linked to pulmonary arterial hypertension.