Only one clinical study so far failed to find a link between ANG gene mutations and ALS in an Italian population (Corrado et al., 2007), but one can arguably reason that such study was small (262 ALS patients) in comparison with other reports (with an average of approximately 1,500 ALS patients per study), and that some of the ANG mutations identified may have a lower disease penetrance, similar to other ALS-associated mutations (Valdmanis and Rouleau, 2008). This evidence concerns the gene ANG and amyotrophic lateral sclerosis.