McMurtray et al. [28] studied the frequency of depressive symptoms in 76 patients with SCA1, SCA2, SCA3 and SCA6 detecting significantly higher prevalence among subjects with SCA3 (60%), compared to other SCA subtypes [SCA1 (25%), SCA2 (23%), and SCA6 (27%)]. This evidence concerns the gene CACNA1A and autosomal dominant cerebellar ataxia.