To assess the impact of alterations in AMPAR subunit expression upon the potential functional Ca2+‐permeable versus Ca2+‐impermeable AMPAR identity in each of the ALS patients and control individuals, we initially calculated the ratio of GluA2 subunit mRNA expression with respect to total AMPAR subunit expression (GluA2/GluATOTAL) for each ALS group, where 0 and 1 reflect purely Ca2+‐permeable and Ca2+‐impermeable AMPARs populations respectively (Figure 2C). This evidence concerns the gene GRIA2 and amyotrophic lateral sclerosis.