Autism is a complex neurodevelopmental disorder, characterized by impaired social and executive function, repetitive and stereotyped behaviors and focused interests. Autism has a strong genetic predisposition since there is more than 50% concordance among monozygotic twins while the normal incidence is around 0.2% (Folstein and Rosen-Seidley 2001). A number of genes have been implicated in autism including AMPA, canabinoid and somatostatin receptors (Purcell et al. Neurolog 2001). In an electrophysiological study (Rinaldi, SFN 2005 Abstract), we found that the microcircuit is hyper-connected with hypoexcitable pyramidal neurons in an animal model of autism – prenatal exposure to valproic acid (VPA, Ingram et al. NeuroToxicol Teratol 2000). Reverse predictions implicate the expression of Kv2.2, Kv3.3, SK2 and Ca1A ion channels in the hypoexcitability. We studied the changes in gene expression at the single cell level in this model for autism using oligonucleotide microarrays and real time PCR. For this purp...