ATXN2 and spinocerebellar ataxia type 2: Even though sensory abnormalities due to dorsal root ganglia damage are well recognised in all three SCAs, they seem to appear earlier and to be more severe in SCA2.39 Indeed, Velázquez-Pérez et al (2014) report that sensory complaints and abnormal sensory nerve conduction studies are already present in a significant proportion of preataxic SCA2 carriers and progress over time.40