This multicentre, intercontinental observational study examined 661 assessments from 219 patients with spinocerebellar ataxia 27B (SCA27B), alongside 390 healthy controls, to investigate the Scale for the Assessment and Rating of Ataxia (SARA), longitudinal progression and potential modifiers of disease severity. Overall progression was 0.54 SARA points per year. Gait, stance and lower-limb impairment were the principal contributors to ataxia severity, while ageing-related motor variability and comorbidities affected assessment. The study also found that larger GAA repeat expansions on the shorter FGF14 allele were associated with faster progression.
