RAI1 and spinocerebellar ataxia type 2: It is also possible to suggest that RAI1 might have a role modulating some aspects of neuron function or differentiation since in addition to its contribution in both SMS and PTLS phenotypic outcome, it is highly expressed in neurons, its expression is influenced by retinoic acid and has polyglutamine polymorphisms that have been found to be associated with schizophrenia and spinocerebellar ataxia type 2.