In this investigation, gene–environment–gender interaction effects in predicting child borderline personality disorder symptomatology among maltreated and nonmaltreated low-income children (N = 1,051) were examined. In the context of a summer research camp, adult-, peer-, and self-report assessments of borderline precursor indicators were obtained, as well as child self-report on the Borderline Personality Features Scale for Children. Genetic variants of the oxytocin receptor genotype and the FK506 binding protein 5 gene CATT haplotype were investigated. Children who self-reported high levels of borderline personality symptomatology were differentiated by adults, peers, and additional self-report on indicators of emotional instability, conflictual relationships with peers and adults, preoccupied attachment, and indicators of self-harm and suicidal ideation. Maltreated children also were more likely to evince many of these difficulties relative to nonmaltreated children. A series of analyses of covariance, controlling for age and ancestrally informative markers, indicated significant Maltreatment × Gene × Gender three-way interactions. Consideration of the maltreatment parameters of subtype, onset, and recency expanded understanding of variation among maltreated children. The three-way interaction effects demonstrated differential patterns among girls and boys. Among girls, the gene–environment interaction was more consistent with a diathesis-stress model, whereas among boys a differential-sensitivity interaction effect was indicated. Moreover, the genetic variants associated with greater risk for higher borderline symptomatology, dependent on maltreatment experiences, were opposite in girls compared to boys. The findings have important implications for understanding variability in early predictors of borderline personality pathology.

Nonsuicidal self-injury (NSSI) is a common behavior among females that has been shown to confer risk for continued self-injury and suicidal attempts. NSSI can be viewed conceptually as behavior that is pathognomonic with aggression and/or depression. Empirical research on concurrent correlates supports this concept: numerous and diverse factors are shown to be significantly associated with self-harm, including depression, emotion dysregulation, impulsivity, and aggression and other conduct problems, as well as environmental stressors such as bullying, harsh parenting, and negative life events. In the present study, we test hypotheses regarding developmental precursors (measured from ages 8 to 12 years) to NSSI in young adolescent girls (ages 13–14 years), specifically whether aggression, depression, and environmental stressors distinguish girls with and without self-harm, and whether there is evidence for multiple developmental pathways to NSSI. Data were derived from the longitudinal Pittsburgh Girls Study. In this community sample of girls, the prevalence of NSSI at ages 13 or 14 years of age was 6.0%. Initial levels in dimensions measured within the depression, aggression, and environmental stressor domains accounted for variance in NSSI in early adolescence. Changes over time in relational aggression and assertiveness were also significantly associated with risk for NSSI. To a large extent, adolescent NSSI was predicted by psychological deficits and stress exposure that began early in childhood. Risk indices were calculated using the 85th or 15th percentile. Close to 80% of girls who engaged in NSSI during adolescence were identified by at least one risk domain in childhood. A sizable proportion of adolescent girls who later engaged in NSSI had childhood risk scores in all three domains; the remaining girls with adolescent NSSI were relatively evenly distributed across the other risk domain profiles. The observation that multiple pathways to NSSI exist suggests that deficits underlying the behavior may vary and require different modes of prevention.

Dispositional trait frameworks offer great potential to elucidate the nature and development of psychopathology, including the construct of relational aggression. The present study sought to explore the dispositional context of relational aggression across three dispositional frameworks: temperament, personality, and personality pathology. Participants comprised a large community sample of youth, aged 6 to 18 years (N = 1,188; 51.2% female). Ratings of children's relational aggression, temperament, personality, and personality pathology traits were obtained through parent report (86.3% mothers). Results showed convergence and divergence across these three dispositional frameworks. Like other antisocial behavior subtypes, relational aggression generally showed connections with traits reflecting negative emotionality and poor self-regulation. Relational aggression showed stronger connections with temperament traits than with personality traits, suggesting that temperament frameworks may capture more relationally aggressive content. Findings at the lower order trait level help differentiate relational aggression from other externalizing problems by providing a more nuanced perspective (e.g., both sociability and shyness positively predicted relational aggression). In addition, there was little evidence of moderation of these associations by gender, age, or age2, and findings remained robust even after controlling for physical aggression. Results are discussed in the broader context of conceptualizing relational aggression in an overarching personality-psychopathology framework.