C9ORF72-ALS exosome toxicity was partly attributed to microRNAs in the exosomes [196], which is likely specific to the C9ORF72-ALS subtype as expression profiling of exosomal microRNAs from SOD1G93A mouse astrocytes showed no significant changes compared to wild-type [195]. Here, C9orf72 is linked to amyotrophic lateral sclerosis.