Of all cases, 95–99% are due to 21-hydroxylase deficiency (21OHD) with defective 21-hydroxylase enzyme, resulting in impaired production of cortisol and varied degree aldosterone, in addition to increased synthesis of adrenocorticotropic hormone (ACTH), steroid precursors, and adrenal androgens [1–5]. The gene discussed is POMC; the disease is classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency.