Social Anxiety and Common OXTR Gene Variant are Associated with Cortisol Response Following Peer Social Challenge

Peer rejection and acceptance experiences are commonplace with potential to promote emotional and adrenocortical stress reactivity. Risk for heightened stress reactivity during these social challenges may be influenced by individual differences in social interaction anxiety (SIA) and the common gene variant, OXTR rs53576, but this relationship remains to be elucidated. We tested the relationship between SIA, OXTR rs53576, and cortisol stress response over time in 53 young adults (Mage=20.13yrs) using an experimental design. Participants were randomized to receive either scripted rejection or acceptance from a group of peer confederates. Saliva samples were collected pre- and post-evaluation and assayed for cortisol. In the peer rejection condition, participants showed significantly lower cortisol responses over time when social interaction anxiety levels were not elevated (versus elevated), and when possessing the GG genotype (versus AA/AG). In the peer acceptance condition, when SIA was not elevated, the GG genotype was associated with significantly lower cortisol responses than the AA/AG genotype. Individual differences in SIA and OXTR 53576 are related to cortisol responses to peer social stressors, with non-elevated levels of SIA and the GG genotype generally contributing to reduced cortisol responsiveness.