We did not so far observe any obvious toxicity of wild-type or mutant FUS-GFP at least at the larval stage in zebrafish, although transgenic zebrafish models expressing ALS mutant TDP-43 or SOD1, exhibit aberrant axonal branching, shortening of axons and an aberrant motor phenotype at later stages of development [30], [31]. The gene discussed is SOD1; the disease is amyotrophic lateral sclerosis.