FXN and Friedreich ataxia: However, it is our consideration that the YG8sR mice could be of greatest use to investigate potential FRDA therapies that specifically target the human FXN gene sequence to increase frataxin expression, including DNA- or RNA-based oligotherapies (Sandi et al., 2013) and TALE-VP64 targeting of the FXN promoter (Chapdelaine et al., 2013).