CACNA1A and autosomal dominant cerebellar ataxia: Consistent with one previous large series study in Taiwan (Soong et al., 2001), our study demonstrated that SCA3 was the most common subtype of SCA, accounting for 102 cases (54.5%), followed by SCA2 (62, 33.2%), SCA1 (11, 5.9%), SCA6 (7, 3.7%), and SCA17 (5, 2.7%).