This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ataxic Disorders, Subject name: Medicine
[{'content': "Fredrich's ataxia is caused by which type of mutation- \nSelect and explain. \nA. Point mutation, B. Expanded trinucleotide repeat, C. Missense mutation, D. Inversion", 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Expanded trinucleotide repeat o Freidrich ataxia is an autosomal recessive disorder.o It is caused by loss of functional mutation in frataxin gene (FxN) gene.o Frataxin gene is located on chromosome 9ql 3.o Majority of patients have an expanded trinucleotide repeat in intron 1 of both alleles of frataxin gene.", 'role': 'assistant'}]