GSR and Friedreich ataxia: Figure 1 shows that expression and activity of CAT (Panels A and C) and GR (Panels B and D), two enzymes involved in cellular antioxidant responses, were low in lymphoblasts mutated for the FANC-A gene with respect to the FA-corr cells, confirming the inability of FA cells to counteract the oxidative stress production by enhancing the antioxidant defenses [13].