For example, SMN, FUS and TDP-43 all have other axonal functions that are impaired in SMA and ALS, such as control of genes that are involved in neuritogenesis and axonal outgrowth that could further contribute to the neurodegenerative phenotype 155, 156, 157, 158, 159. This evidence concerns the gene TARDBP and amyotrophic lateral sclerosis.