This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc. (R.B.C), Subject name: Pathology
[{'content': 'In HbM the position of point mutation \nSelect and explain. \nA. b chain, 87th codon, Histidine - Tyrosine, B. a chain, 87th codon, Histidine - Tyrosine, C. b chain, 6th codon, Glutamine - Valine, D. b chain, 6th codon, Glutamine - Lysine', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (b) a chain, 87th codon, Histidine - Tyrosine(Ref: Wintrobes 12th ed 1060-1070)M (met) hemoglobins are characterized by heme-iron oxidation and result in cyanosis.HbM Iwate (HBA 87th position his - tyr)', 'role': 'assistant'}]