First, mutations in several genes that are directly involved in cytoskeletal homeostasis including ALS2, DCTN1, KIF5A, NF-L, NF-H, PFN1, PRPH, SPAST, and TUBA4A can cause or are associated with an increased incidence of ALS (78–90). The gene discussed is PFN1; the disease is amyotrophic lateral sclerosis.