Male and female healthy volunteers between the ages of 21 and 30 were recruited for participation via newspaper, radio and other advertisements from the greater Baltimore area. Subjects who appeared to qualify for research participation based on a telephone screen were invited for an interview. Subjects provided written informed consent using a Johns Hopkins Institutional Review Board approved informed consent document and then completed an in-person assessment interview with a Masters-level research assistant with experience in administrating structured diagnostic interviews. The interview included the Mini-International Neuropsychiatric Interview (M.I.N.I.) (Sheehan et al., 1998) and/or the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA)(Bucholz et al., 1994) to assess the presence or absence of drug and alcohol problems as well as other Axis I DSM IV disorders. Subjects completed a medical examination, with standard laboratory tests (i.e., complete blood count, comprehensive metabolic panel, and urinalysis), and an alcohol breathalyzer test and urine toxicology screen. Recent patterns of alcohol consumption were determined via the 90-day Time Line Follow Back (TLFB) (Sobell and Sobell, 1992) administered by research staff who complete rigorous training and
