To investigate a possible relationship between DPR and nucleolar cavities in postmortem human brain we used FFPE tissue sections from the cerebellum from c9orf72-related FTLD-TDP (c9FTLD, N = 17) and c9orf72-related ALS patients (c9ALS, N = 11) (see supplementary Table 2), immunostained with an antibody against poly(GA)—the most toxic and aggregation-prone DPR [27, 53]—as well as with pTDP-43 and pTau antibodies. The gene discussed is C9orf72; the disease is amyotrophic lateral sclerosis.