Abnormal cytoplasmic accumulation of fused in sarcoma (FUS) protein is the pathological hallmark of some cases of amyotrophic lateral sclerosis (ALS) with transactive response DNA‐binding protein of 43KDa (TDP‐43)‐negative pathology that lack SOD1 mutations. The gene discussed is SOD1; the disease is amyotrophic lateral sclerosis.