FGF14 and cerebellar ataxia: While FGF14 GAA repeat expansions have recently been shown to be a common cause of spinocerebellar ataxia (SCA27B)—which is associated with DBN in up to 40–60% of patients1,3,4,24—, the high frequency of FGF14 (GAA)≥250 repeat expansions in patients with a non-ataxic DBN presentation was unexpected.