Gene networks showing inter-relationship between differentially expressed genes in LCL from 3 discordant autistic twin sets using Ingenuity Pathways Analysis software. The over-expressed (red) and under-expressed (green) genes were identified as significant using SAM analysis (FDR = 26.4%) of microarray data across 3 twin pairs. The log2 expression ratio cutoff was set at ± 0.58 and was based upon the mean values for each gene. Genes within this network that have a reported role in nervous system development and function are marked with a "#" symbol and include: ASS, ALOX5AP (FLAP), DAPK1, F13A1, IL6ST, NAGLU, PTGS2, and ROBO1. Gray genes are present but do not meet expression cutoff.