ITPR1 and cerebellar ataxia: Several classes of spinocerebellar ataxia in humans and mice are associated with reduced IP3R1 levels (Matsumoto et al., 1996; Street et al., 1997; Zecevic et al., 1999; Lin et al., 2000; Ogura et al., 2001; Serra et al., 2004; Kurnellas et al., 2007; van de Leemput et al., 2007; Chou et al., 2008; Novak et al., 2010b; Castrioto et al., 2011; Marelli et al., 2011; Huang et al., 2012; Obayashi et al., 2012; Hansen et al., 2013; Sugawara et al., 2013) or increased sensitivity of the receptor to IP3 (Inoue et al., 2001; Chen et al., 2008; Liu et al., 2009), or both.