Researchers have suspected for years that chronic alcohol abuse and alcoholism change the programming of the human brain at the molecular level, particularly in the regions involving judgment and decision-making. In fact, during the past several decades, cell and animal studies have consistently indicated that changes in gene expression in the brain appear to be responsible for the tolerance, dependence, and neurotoxicity produced by chronic alcohol abuse.1 Until recently, however, technological limitations prevented any kind of large-scale approach to confirm this hypothesis.
"As research has evolved over the past five years or so, a consensus emerged that neuroadaptation to drugs, which is part of drug addiction--aspects such as development of tolerance to the drug action, or development of physical dependence--likely are caused by changes in gene expression; but until the gene arrays came along, it was a real needle in a haystack to try and find which gene might...