FGF14 and cerebellar ataxia: We divided patients with cerebellar ataxia for whom detailed clinical information was available into two main groups: 1) patients with at least one large allele ≥ 250 AAG repeats (n = 42; ‘SCA27B-positive patients’) and 2) patients with both alleles < 180 AAG repeats or composed of AAGAG repeats (group referred to as ‘SCA27B-negative patients’) (n = 98; Supplementary Data 5).