Compared to isogenic control astrocytes, FUS-ALS astrocytes were found by a variety of techniques, including immunocytochemistry, RNA sequencing, and calcium transient hyperactivity, to display elevated glial fibrillary acidic protein (GFAP) expression, cytoplasmic FUS mislocalization, the production of inflammatory cytokines, and enhanced spontaneous reactivity. Here, GFAP is linked to amyotrophic lateral sclerosis.