Ninety-five percent of FRDA patients are homozygous for a GAA triplet expansion in the first intron of the FXN gene; this leads to transcriptional silencing of FXN through heterochromatinization of the expanded region and to reduced expression of frataxin, a ubiquitous and highly conserved mitochondrial protein [1, 6, 7]. The gene discussed is FXN; the disease is Friedreich ataxia.