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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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Thalassaemia major manifests in
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The correct answer is  Beta thalassemia major manifests 6 to 9 months after bih as Hb synthesis switches from HbF to HbA. Beta thalassemia is caused by the mutation that diminishes the synthesis of beta globin chain seen in HbA. The red cells may completely lack HbA or contain small amounts. Reference: Robbins and Cotran Pathologic basis of disease.South Asia Edition,-9 volume 1.page no. 638-639