Fredrich's ataxia is caused by -

Ans. is 'b' i.e., Expanded trinucleotide repeat o Freidrich ataxia is an autosomal recessive disorder.o It is caused by loss of Junctional mutation in frataxin gene (FxN) gene.o Frataxin gene is located on chromosome 9ql3.o Majority of patients have an expanded trinucleotide repeat in intron 1 of both alleles of frataxin gene.