This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
[{'content': "The nucleotide triplet CTC in the sixth position of the l3-chain in DNA forms the complementary nucleotide on (mRNA) that codes for glutamic acid. A point mutation on the l3-chain resulting in the nucleotide triplet CAC forms a com¬plementary nucleotide on mRNA that codes for valine. In sickle cell anemia, you would expect the comple¬mentary nucleotide triplet on mRNA from 5' to 3' to read \nSelect and explain. \nA. GAG, B. CTC, C. GTG, D. GUG", 'role': 'user'}, {'content': 'Answer: D \nExplanation: Note that by changing the CTC triplet to a CAC, the messenger RNA (mRNA) changes from GAG, which normally codes for glutamic acid in the sixth position of the \uf062-chain of hemoglobin, to GUG, which now codes for valine. This point mutation of a single base pair is responsible for sickle cell anemia.', 'role': 'assistant'}]