was over when interactions were not supervised by group leaders. In our sample, 70% of the youth remained in or continued on to the same school as the majority of participants in their intervention group at the one-year follow-up. The middle school environment may further facilitate the maintenance of new affiliations, as students are less monitored by teachers, have less consistency in the adult who monitors them, and have more time for unsupervised child interactions (Bradshaw, O’Brennan, & McNeely, 2008; Wilson, 2004). Furthermore, children may also maintain affiliations via social media. In contrast, individuals with the A allele may have been less affected by the exposure to deviant peers while in the group, and less likely to establish and maintain bonds with these peers once the intervention was over.
