total number of DSM-IV abuse and dependence symptoms, and number of unsuccessful quit attempts. The four phenotypes were chosen to capture quantitative measures of alcohol-specific behaviors. It is worth noting that the last three of these phenotypes are lifetime measures whereas average drinks measures past year use. Data were available for these items on 980 people. Ten individuals reported having tried alcohol but did not answer other alcohol related questions. Average number of drinks was assessed by the question: “On days when you drank alcoholic beverages in the past year, on average how many drinks would you have?”. Number of quit attempts was assessed with the question “How many times were you unable to quit or cut down?”, after the individual had indicated desire to and being unable to quit or cut down in the past. Finally, number of blackouts was assessed with the question “How many blackouts have you had?”, which was asked only if the individual had said yes to the question: “Have you ever had blackouts while drinking, that is where you drank enough so that you couldn't remember the next day what you had said or done?”. Following the initial test of association with the composite
