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 sickle cell anemia defect is in which chain? \nSelect and explain. \nA. a-chain, B. b-chain, C. Both the chains, D. None of these', 'role': 'user'}, {'content': 'Answer: B \nExplanation: 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.', 'role': 'assistant'}]