The best thresholds of ATXN2 and ATXN1 were the same as the intermediate thresholds established in spinocerebellar ataxia type 2 and type 1, i.e. larger than 29 and 33 repeat units, respectively, though this was only significant for ATXN2 (OR = 4.2, 95% CI = 2.3–8.7, PFDR = 5.7 × 10–6).27,33  ATXN2 was also significantly associated with ALS between 28–32 repeat units (OR = 3.0–7.5, 95% CI = 1.9–36, PFDR = 1.4 × 10−4–8.5 × 10−6; Fig. S14). This evidence concerns the gene ATXN1 and spinocerebellar ataxia type 2.