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. The gene discussed is CHST2; the disease is amyotrophic lateral sclerosis.