SACS and spastic ataxia: In CANVAS17, two variants (GenBank: NM_001278055; c.12398delT [p.Phe4133Serfs∗28] and GenBank: NM_001278055; c.5306T>A [p.Val1769Asp]) were identified in the gene encoding sacsin (SACS) and segregation analysis confirmed they were in trans. Biallelic mutations in SACS cause spastic ataxia of the Charlevoix-Saguenay type (MIM: 270550).