It is difficult to discern which of the aforementioned findings with adult samples best translates to an adolescent population. Silberg, Ritter, D’Onofrio, and Eaves (2003) conducted a prospective follow-up study to examine genetic risk factors for substance abuse in same-sex twin pairs ages 12 to 17. Since the study was targeting the progression of alcohol use in youth, the authors considered alcohol use to be present if either the parent or child endorsed at least one alcohol drink in the past three months without parental permission. Results indicated that girls’ alcohol involvement, both the initiation and continuation of use, was largely influenced by genetic factors. Conversely, environmental factors were more influential on the continuation of boys’ drinking over time. The effect of genes on use for male teens was limited to early use of alcohol.
