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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
Complete deficiency of UDP glucoronyl transferase (UGT) is seen in:
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The correct answer is  UGT1A1, generated from the UGT1A1 gene, is responsible for bilirubin glucuronidation. Mutations of UGT1A1 cause hereditary unconjugated hyperbilirubinemias: Crigler-Najjar type 1 is caused by severe UGT1A1 deficiency and is fatal around the time of bih, Crigler-Najjar type II and Gilbe syndrome there is some UGT1A1 activity and the phenotypes are much milder