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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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In congenital adrenal hyperplasia most common deficiency
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The correct answer is  Ans) a (21- alpha ) Ref Nelson 18'h ed p 2360More than 90% of CAH cases are caused by 21 -hydroxylase deficiency.