Friedreich ataxia (FRDA) is an autosomal recessive neurodegenerative disease caused by reduced expression levels of the frataxin gene (FXN) due to expansion of triplet nucleotide GAA repeats in the first intron of frataxin.The important roles for frataxin were played in mitochondrial iron storage,regulation of intracellular iron trafficking,iron-sulfur (Fe-S) cluster and heme biogenesis,removal of reactive oxygen species,and reactivation of the labile Fe-S cluster of mitochondrial aconitase.The central and peripheral nervous systems and heart are among the most severely affected tissues,and more than half of those afflicted eventually succumb to cardiac-related complications.