FXN and Friedreich ataxia: Epigenetics as a therapeutic approach for FRDA has been extensively explored and notably, HDACi (2-aminobenzamide–type histone deacetylase inhibitors) increased FXN expression in peripheral blood mononuclear cells of patients enrolled in a Phase I clinical trial with a promising safety profile (Rai et al., 2010; Soragni et al., 2014; Polak et al., 2016; Soragni and Gottesfeld, 2016).