A downregulation of Itpr1 and Inpp5a expression at the transcript level was already reported for several other SCA mouse models: Sca1[82Q] transgenic mice [52, 61], Sca1−/− and Sca1154Q/+ mice [62], as well as Sca3[Q79] transgenic (only Itpr1) [63] and Sca7266Q/+ mice (only Inpp5a) [64]. This evidence concerns the gene INPP5A and autosomal dominant cerebellar ataxia.