Heterozygous missense variants in the SPTBN2 gene, encoding the non-erythrocytic beta spectrin 2 subunit (beta-III spectrin), have been identified in autosomal dominant spinocerebellar ataxia type 5 (SCA5), which is a rare adult-onset neurodegenerative disorder that is characterized by progressive cerebellar ataxia [46,47,48,49]. The gene discussed is SPTBN2; the disease is spinocerebellar ataxia type 5.