In ALS, miRNAs are of special interest, because several causative genes, such as TARDBP [57, 58], FUS [59], HNRNPA1 [60], HNRNPA2B1, or MATR3 [61], have been linked to miRNA biogenesis and/or function, and even a general defect of miRNA biogenesis is discussed [62]. This evidence concerns the gene FUS and amyotrophic lateral sclerosis.