The primary goal of the present study was to test for association between AD and several alcohol-related quantitative traits, such as initial sensitivity (ISENS), and SNPs in 10 DA genes in a large, homogeneous sample. Because twin studies have found that a single genetic factor is largely responsible for the genetic susceptibility to AD and several other disinhibitory phenotypes and traits, a second goal of the study was to test for association of these SNPs with relevant symptoms of disinhibitory disorders as well as a disinhibitory factor score. To our knowledge, we are the first group to report results on an association analysis of both quantitative alcohol-related traits and symptoms of disinhibitory disorders within alcohol-dependent cases for a large group of DA-related genes.
