Furthermore, the current study suggests that Cic is the regulator for this module, which not only establishes a novel role for Cic as a regulator of excitability in Purkinje neurons but also provides a mechanistic link between polyglutamine-expanded ATXN1 and abnormal Purkinje neuron physiology in SCA1. The gene discussed is ATXN1; the disease is spinocerebellar ataxia type 1.