Fall frequency has been reported to be associated with disease duration, ataxia severity, presence of pyramidal symptoms, total number of non-ataxia symptoms (including hyperreflexia, areflexia, extensor plantar reflex, spasticity, paresis, muscle atrophy, fasciculation, myoclonus, rigidity, chorea/dyskinesia, dystonia, resting tremor, sensory symptoms, urinary dysfunction, cognitive dysfunction, and brainstem oculomotor signs), and the genotype of SCA3 in patients with SCA by correlation analysis (2, 3). The gene discussed is ATXN3; the disease is drug-induced dyskinesia.