We also tested the DA genes for association with scores for disinhibitory disorders. Symptom counts for alcohol dependence (ADsx, range 3 to 7) were assessed using the Semi-Structured Assessment of the Genetics of Alcoholism (SSAGA, version 11, Bucholz et al., 1994), modified to reduce assessment time. Counts for illicit substance use drug dependence (DDsx, range 0 to 7), conduct disorder (CDsx, range 0 to 14), and antisocial personality disorder (ASPDsx, range 0 to 9) were collected using adapted versions of the Structured Clinical Interview for the DSM-IV Disorders (SCID, Spitzer and Williams, 1985). Drugs assessed as part of substance use included cannabis, sedatives, stimulants, cocaine, opiates, hallucinogens, and other drugs (e.g., steroids, nitrous oxide). All drugs were considered illicit in this context because the subjects were asked only about nonmedical use (e.g., use without a prescription, use in greater amounts/more often than was prescribed, or use not in the intended manner). Other measures include retrospective reports of childhood attention deficit/hyperactivity disorder (ADHDsx) using items from Wender’s Childhood Problem Behavior Checklist (Wender, 1971) and novelty seeking scores (NS) using the 18-item
