We confirmed that this assay was sensitive to ALS-related genetic lesions in our hands by delivering mRNA encoding human SOD1 with or without mutations associated with familial ALS (5.7 and 0.18 primary motoneurons affected per fish injected with SOD1A4V or SOD1WT, respectively p<0.05), consistent with past results [26], [27]. Here, SOD1 is linked to amyotrophic lateral sclerosis.