Friedreich's ataxia is thus believed to be a mitochondrial disease caused by a mutation in the nuclear genome (specifically, expansion of an intronic GAA triplet repeat in the  FXN gene, which encodes the protein frataxin. ).
Friedreich's ataxia is viewed as a mitochondrial condition brought on by a genetic mutation in the nuclear genome (particularly, the expansion of an intronic GAA triplet repeat in the FXN gene, which generates the frataxin protein).