Leveraging ACTH (n = 62) and cortisol (n = 66) concentrations from 51 (20 pediatric, 31 adult) untreated CAH patients, and assuming maximal cortisol production (Emax) = 100% in healthy individuals, residual enzymatic activity was estimated as an Emax scaling factor. Here, POMC is linked to congenital adrenal hyperplasia.