Description
The mammalian forebrain is a tissue of stunning complexity comprised of numerous regions each containing many distinct cell types that differ in their intrinsic and synaptic physiology, morphology and connectivity. These differences are likely conferred by differential gene expression, but the extent and nature of cell type specific gene expression is largely unknown. Here, we carried out microarray analysis of twelve major classes of fluorescently labelled neurons within the forebrain and provide the first comprehensive view of gene expression differences. The results demonstrate a profound molecular heterogeneity among neuronal subtypes, represented disproportionately by gene paralogs, and begin to reveal the genetic programs underlying the fundamental divisions between neuronal classes including that between glutamatergic and GABAergic neurons.