In HbM the position of point mutation: (A) 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
Answer is B. 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)