exposure in turn produces changes in gene expression, which are believed to contribute, together with epigenetic alterations and post-translational modifications, to the long-term allostatic changes in the activity of brain emotional systems that underlie alcoholism [3]. Exploration of ethanol-responsive genes in the brain is therefore expected to provide insights into the molecular mechanisms underlying compulsive drinking and relapse. These transcriptional changes are however anticipated to affect a broad set of genes, whose concerted regulation may orchestrate the complex behavioral outcome characterizing alcoholism. Gene expression profiling approaches are well suited to address this complexity because they enable hypothesis-free survey of transcriptional changes at a genome-wide scale.
