In C9orf72-ALS, few studies have described a cell-autonomous astrocyte pathology and an astrocyte-mediated non-cell autonomous motor neuron pathology (Madill et al., 2017; Allen et al., 2019; Birger et al., 2019; Taga et al., 2019; Varcianna et al., 2019; Zhao et al., 2020). Here, C9orf72 is linked to amyotrophic lateral sclerosis.