描述
Hyperprolinemia type I (HPI, proline oxidase deficiency) is caused by mutation in the proline dehydrogenase gene (PRODH), which codes for proline dehydrogenase (proline oxidase). This enzyme converts proline to delta-1-pyrroline-5-carboxylate. A defect in proline dehydrogenase causes accumulation of proline in plasma, and glycine, hydroxyproline, and proline in urine. Symptoms include mental retardation, renal cysts, and seizures.