In sickle cell anemia defect is in which chain?: (A) a-chain, (B) b-chain, (C) Both the chains, (D) None of these
Answer is B. Ans. (b) b-chain(Ref: 9th/pg 635-636; 8th/pg 645-647)In sickle cell anemia defect is: point mutation in the6th codon of b-globin Q that leadsto there placement of a glutamate residue with a valine residue. QLeading to: Abnormal physiochemical properties(Solubility defect) Q of the resulting sickle hemoglobin (HbS)Promotes the polymerization of deoxygenated haemoglobinLeading to red cell distortionHemolytic anemia, microvascular obstruction, and ischemic tissue damage.