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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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PKU is a congenital amino acid metabolic disorder. In one of the following rare variants of PKU Dihydro Biopterin synthesis is affected. The enzyme deficient is
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The correct answer is  Atypical form of phenylketonuria is due to deficiency of dihydrobiopterin reductase which is required for converion of H2-biopterin intorin. H4-biopterin is required for oxidation of phenylalanine because it is a cofactor for phenylalanine hydroxylase.