TPP1 and cerebellar ataxia: Reduced TPP1 activity is implicated in other heterogeneous autosomal recessive ataxias such as SCAR7 the phenotype previously described as Type 7 Autosomal Recessive Spinocerebellar Ataxia or other atypical presentations of CLN2 disease [34]; thus the diagnostic workup for unexplained spinocerebellar ataxias should also include analysis of TPP1 enzyme activity.