(A) In situ hybridizations and expression quantification from Allen Brain Atlas (ABA; Lein et al., 2007) indicate expression patterns of autism spectrum disorder (ASD)-related genes in the cerebellar cortex (cctx), the deep cerebellar nuclei (DCN), the red nucleus and inferior olive (RN/IO), and the facial nucleus and the trigeminal nucleus (FN/TN). Displayed here are Shank3, Mecp2, Cntnap2, and Tsc1. Note that one gene in the imprinted region 15q11-13 with disease linkage (Albrecht et al., 1997; Piochon et al., 2014), Ube3a, with is also shown. Scale bars, 200 μm. P41 to adult data include P56 data from the Allen Brain Atlas. (B) Top: the canonical cerebellar circuit. Input along the CS (blue) pathway via mfs from the pontine nuclei enters the cerebellar cortex through granule cells (GrC), which receive feedforward and feedback inhibition from Golgi cells (GoC) in the granule cell layer. GrCs send pf projections to PC dendritic arbors. PCs also receive teaching signals along the US (gray) pathway via cfs from the inferior olive. The output of clustered PCs (gray) converges onto neurons in the cerebellar nuclei (DCN), which drive downstream neurons in the output pathway. Bottom: gene expression from birth to adulthood, by cell type. Full bars indicate strong expression as found in the literature. White bars indicate little or no expression, and a horizontal thin line indicates no data available. The hashed bar indicates the period during which Tsc1 is expressed in wild-type animals but knocked out in the L7-Tsc1 animals. References: Shank3 (Böckers et al., 2004; Böckers et al., 2005), Mecp2 (Shahbazian et al., 2002b; Mullaney et al., 2004; Neul and Zoghbi, 2004; Dragich et al., 2007; Schmid et al., 2008), Tsc1 (Tsai et al., 2012), Ube3a (a gene strongly implicated in neurodevelopmental disorders in locus 15q11-1: Albrecht et al., 1997; Dindot et al., 2008), Cntnap2 (Fujita et al., 2012; Paul et al., 2012).