Nonetheless, the two forms are clinically indistinguishable with an average disease onset at ∼50 years [27, 28], notable exceptions are patients with mutations in the ALS‐associated genes such as the SOD1‐A4V variant [29], or the FUSc.1574C>T (P525L) and c.1554_1557delACAG mutations [30] that show distinct phenotypes and an early onset. The gene discussed is SOD1; the disease is amyotrophic lateral sclerosis.