Autosomal-recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a progressive neurodegenerative disorder (Bouchard et al., 1978) caused most often by a deletion mutation in the SACS gene encoding the large (521 kD) protein sacsin (Engert et al., 2000) that functions as a chaperone (Parfitt et al., 2009) and regulates the cytoskeleton (Duncan et al., 2017; Gentil et al., 2019). Here, SACS is linked to Autosomal recessive spastic ataxia of Charlevoix-Saguenay.