We examined whether the oxytocin receptor gene (OXTR) single nucleotide polymorphism (SNP) rs53576 genotype buffers the combined impact of negative social environments (e.g., interpersonal conflict/constraint) and economic stress on post-traumatic stress (PTS) symptoms and impaired daily functioning following collective stress (September 11th terrorist attacks). Saliva was collected by mail and used to genotype 704 respondents. Participants completed Web-based assessments of pre-9/11 mental health, acute stress 9-23 days after 9/11, the quality of social environments 1 year post-9/11, economic stress 18 months post-9/11, and PTS symptoms and impaired functioning 2 and 3 years post-9/11. Interactions between negative social environments and economic stress were examined separately based on OXTR rs53576 genotype (GG vs. any A allele). For individuals with an A allele, a negative social environment significantly increased PTS symptoms without regard to the level of economic stress experienced. However, for respondents with a GG genotype, negative social environments predicted elevated PTS symptoms only for those also experiencing high economic stress. Gender moderated associations between negative social environments, economic stress, and impaired functioning. The functioning of females was most affected by negative social environments regardless of genotype and economic stress, whereas the functioning of males was differentially susceptible to economic stress depending on OXTR genotype and negative social environments. These findings suggest that it is important to consider the combined impact of gender and ongoing stress in different domains as moderators of genetic vulnerability following collective stress.

The goal of the current study was to examine conflict appraisals and diurnal cortisol production as mediators of the robust association between marital conflict and adolescent adjustment problems. Parents reported their marital conflict and were observed engaging in a marital conflict discussion; they also reported adolescent internalizing and externalizing behaviors. Adolescents (n = 105, 52% female, 10–17 years of age) appraised their parents’ marital conflict and reported their internalizing and externalizing behaviors. After the laboratory visit, adolescents provided four saliva samples on each of 2 consecutive days to assess diurnal cortisol production. More-negative marital conflict predicted more self-blame for parental conflict, which in turn predicted less robust decreases in cortisol across the day. Further, this flattened cortisol production pattern mediated the relationship between greater self-blame for parental conflict and adolescents’ elevated internalizing behaviors. Feeling responsible for parental conflict appears to be particularly damaging in terms of physiological regulation and adjustment, and may therefore be a particularly useful intervention target.