FXN and Friedreich ataxia: Interestingly, a prevalent point mutation in FRDA, a single nucleotide change (c.389G>T) resulting in a missense substitution at amino acid 130 of glycine to valine (G130V), is associated with a milder clinical presentation and slower disease progression than most FRDA cases arising from homozygous GAA repeat expansions (Bidichandani et al., 1997; Clark et al., 2017; McCabe et al., 2000; Puccio and Koenig, 2000).