The majority of previous reports, in both animals and humans, included only male subjects. Gender is an important element when studying substance use. For instance, in humans males begin drinking regularly and heavily much earlier than females; men also consume larger amount of alcohol daily than women (Prescott et al., 2005). Although women have a lower incidence of AD than men, on average, they develop alcohol dependence after a shorter duration of chronic drinking and show withdrawal following consumption of smaller volumes of ethanol. Some studies suggest that male and female alcoholics show differences in brain changes and negative consequences due to alcohol abuse (Pfefferbaum et al., 2001; Wuethrich, 2001). However, lack of genetic association data in female alcoholism is a weakness in the literature. The first aim of the present study was to test the association of GAD genes with AD in a different and larger independent sample. Given the differences in the effects of ethanol between males and females noted above, we tested whether there are gender specific effects in the association of GAD genes with AD.
