(Jiang et al., 2019, Ren et al., 2019, Cocozza et al., 2015, Cocozza et al., 2018, Pereira et al., 2017, Hernandez-Castillo et al., 2013, Hernandez-Castillo et al., 2015, Chen et al., 2022) Patients were diagnosed with spinocerebellar ataxia type 2 (SCA2), SCA3, SCA7, SCA6, sporadic adult-onset of ataxia, multiple system atrophy with cerebellar atrophy, and Friedreich’s ataxia. The gene discussed is CACNA1A; the disease is spinocerebellar ataxia type 2.