AFP and Gait ataxia: SETX gene mutations were first reported as a cause of AOA2 by Moreira et al. (2004), they described 15 affected families with onset ages of 10–22 years who presented with gait ataxia, sensory motor neuropathy, cerebellar atrophy and high AFP levels; 15 variants in the SETX gene were identified, comprising five missense mutations, four nonsense mutations and six frameshift mutations (Moreira et al., 2004).