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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.
user
A 6-year-old child is brought to the OPD with a history of mental retardation, failure to walk , failure to grow, seizures, hyperactivity, and tremors. On examination, there is microcephaly, fair hair, light skin color, and blue eyes. Which of the following enzyme is deficient in this child?
assistant
The correct answer is  The given clinical manifestations point to the diagnosis of Phenylketonuria (PKU). Deficiency of the enzyme phenylalanine hydroxylase Reference: Harpers illustrated biochemistry 30th edition