Furthermore, for the first time, we detect p53 interacting with the trinucleotide repeats region of the first intron of frataxin gene folded in vitro into non-B DNA structures and p53 binding to this region in adenocarcinoma cells (MCF7) and Friedreich’s ataxia fibroblast cells (FXN 4654) upon p53 stabilization. The gene discussed is FXN; the disease is Friedreich ataxia.