SOD1 and Spinocerebellar ataxia type 3: There were no differences in the SOD activity between the symptomatic SCA3/MJD and control groups (1.51 U SOD/mg of protein, 95% CI, −0.37 to 3.39, p = 0.165) or the presymptomatic SCA3/MJD and control groups (1.49 U SOD/mg of protein, 95% CI, −1.51 to 4.50, p = 0.700).