The ACOX1 (c.710A>G; p.N237S) gain-of-function mutation (OMIM # 609751.0008) was identified as a putative de novo variant causing Mitchell syndrome (OMIM # 618960), an autosomal dominant, progressive degenerative process involving sensorineural hearing loss, polyneuropathy, cognitive decline, and seizures (5). This evidence concerns the gene ACOX1 and Mitchell syndrome.