KS expression was induced exclusively in a subpopulation of microglia in SOD1(G93A) mice surrounding motoneurons in the ventral horn during the early ALS disease phase when M2 microglia markers were transiently enhanced in SOD1(G93A) mice, but not in SOD1(G93A)GlcNAc6ST‐1(−/−) mice. This evidence concerns the gene SOD1 and amyotrophic lateral sclerosis.