Given that the reduction in the expression level of ADAR2 mRNA begins at the preclinical stage in the motor neurons of sporadic ALS patients [3], age-dependent downregulation of ADAR2 activity may accelerate the expression of the Q/R site-unedited GluA2, thereby playing a role in the age-related increase in the incidence of ALS and the acceleration of the course of disease in ALS patients [3]. Here, GRIA2 is linked to amyotrophic lateral sclerosis.