It has been reported that large caliber axons are preferentially affected by ALS [41], [42], and, indeed, we found a 43% reduction in the number of large caliber axons in SOD1-G93A mice compared with wild-type mice [SOD: 404.2±31.1, WT: 706.5±51.6, p = 0.0005 (Fig. 6D)]. This evidence concerns the gene SOD1 and amyotrophic lateral sclerosis.