This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Molecular Genetics, Subject name: Biochemistry
[{'content': 'Sickle cell anemia is the clinical manifestation of homozygous genes for an abnormal hemoglobin molecule. The event responsible for the mutation in the B chain is: \nSelect and explain. \nA. Insertion, B. Deletion, C. Nondisjunction, D. Point mutation', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. D. Point mutationThe mutation in HbS is an example ofPoint mutationPartially acceptable mis-sense mutationTransversionBase substitution.Nonconservative mutation', 'role': 'assistant'}]