No MRI brain imaging data provided, but all patients tested negative for ALS-associated genetic changes within C9ORF72, SOD1, FUS, and TARDBP. Any patients specifically tested for a clinical diagnosis of spinocerebellar ataxia were not included in this analysis in order to provide prevalence estimates for a typical ALS cohort. This evidence concerns the gene SOD1 and amyotrophic lateral sclerosis.