Huntington’s chorea, a dramatic neurodegenerative disorder is due to an expansion of a CAG triplet repeat within the first exon of the gene encoding the huntingtin protein [18]; myotonic dystrophy type 1 (also called Steinert disease or DM1) is induced by the expansion of a CTG trinucleotide repeat in the 3’ UTR of the DMPK gene [19]; and Friedreich’s ataxia, a recessive neurological disorder characterized by a defect in iron metabolism, is provoked by the expansion of a GAA repeat in the first intron of the FRDA gene [20]. Here, FXN is linked to myotonic dystrophy type 1.