ATXN3 and spinocerebellar ataxia type 2: Overall, the majority of correlations identified were related to spinocerebellar ataxia (SCA) type 2 (SCA2), SCA3, or Friedreich ataxia (FRDA) (see Appendix 3, supplementary table S5 for all 105 significant correlations found in 20 studies), and the strength of correlations was high (n = 36) to moderate (n = 41) in most cases (see Table 5 and Appendix 3, supplementary table S6 for details).