Background In a seminal study of gene-environment interaction, childhood maltreatment predicted antisocial behavior more strongly in males carrying an MAOA promoter variant of lesser, compared to higher, transcriptional efficiency. Many further investigations have been reported, including studies of other early environmental exposures and females. Here we report a meta-analysis of studies testing the interaction of MAOA genotype and childhood adversities on antisocial outcomes in predominantly non-clinical samples. Method Included were 27 peer-reviewed, English-language studies published through August, 2012, that contained indicators of maltreatment or “other” family (e.g., parenting, sociodemographic) hardships; MAOA genotype; indices of aggressive and antisocial behavior; and statistical test of genotype-environment interaction. Studies of forensic and exclusively clinical samples, clinical cohorts lacking proportionally matched controls, or outcomes non-specific for antisocial behavior were excluded. The Liptak-Stouffer weighted Z-test for meta-analysis was implemented to maximize study inclusion and calculated separately for male and female cohorts. Results Across 20 male cohorts, early adversity presaged antisocial outcomes more strongly for low, relative to high, activity MAOA genotype (P=.0044). Stratified analyses showed the interaction specific to maltreatment (P=.0000008) and robust to several sensitivity analyses. Across 11 female cohorts, MAOA did not interact with combined early life adversities, whereas maltreatment alone predicted antisocial behaviors preferentially, but weakly, in females of high activity MAOA genotype (P=.02). Conclusions We found common regulatory variation in MAOA to moderate effects of childhood maltreatment on male antisocial behaviors, confirming a sentinel finding in research on gene-environment interaction. An analogous, but less consistent, finding in females warrants further investigation.

Callous-unemotional (CU) traits have been shown to delineate a unique subgroup of children with severe and persistent conduct problems that seem to have unique etiological origins. However, commonly used measures of CU traits in children may not adequately capture the full range of these characteristics in a developmentally appropriate manner. As a result, the 24-item Inventory of Callous-Unemotional Traits (ICU; self-, parent-, and teacher-report versions; Frick, 2004) was recently developed as a more extensive assessment of CU traits. However, studies to date have focused almost exclusively on the self-report version ICU in adolescents and have identified problems with the factor structure of the measure. The current study is the 1st to examine the factor structure of the parent-report version ICU in a sample of 250 boys (ages 6-12 years) exhibiting significant conduct problems. Initial analyses indicated that factor models reported for the parent-report version of the ICU demonstrated a relatively poor fit to the data. Item response theory techniques were used to develop a more psychometrically sound and efficient short form of the ICU consisting of 2 factors (i.e., Callous and Uncaring) using 12 of the original 24 items. The revised version scores demonstrated high internal consistency, good discrimination across the continuum of the CU construct, and adequate short-term test-retest reliability. The revised measure total score also exhibited evidence of convergent and discriminant validity, although the subscales exhibited some differential correlations with theoretically meaningful constructs. Avenues for future measure refinement and use with children are discussed.

A better understanding of what leads youth to initially engage in antisocial behavior (ASB) and more importantly persist with such behaviors into adulthood has significant implications for prevention and intervention efforts. A considerable number of studies using behavioral and neuroimaging techniques have investigated abnormalities in reward and punishment processing as potential causal mechanisms underlying ASB. However, this literature has yet to be critically evaluated, and there are no comprehensive reviews that systematically examine and synthesize these findings. The goal of the present review is twofold. The first aim is to examine the extent to which youth with ASB are characterized by abnormalities in (1) reward processing; (2) punishment processing; or (3) both reward and punishment processing. The second aim is to evaluate whether aberrant reward and/or punishment processing is specific to or most pronounced in a subgroup of antisocial youth with psychopathic features. Studies utilizing behavioral methods are first reviewed, followed by studies using functional magnetic resonance imaging. An integration of theory and research across multiple levels of analysis is presented in order to provide a more comprehensive understanding of reward and punishment processing in antisocial youth. Findings are discussed in terms of developmental and contextual considerations, proposed future directions and implications for intervention.

There is an urgent need to identify signs that harbinger onset of borderline personality disorder (BPD). Advancement in this area is required to refine developmental theories, discover etiological mechanisms, improve early detection, and achieve our ultimate goal of prevention. Though many studies have supported a wide range of factors that increase subsequent risk for BPD, this literature has yet to be critically evaluated, and there are no comprehensive reviews that examine and integrate these findings. To address this limitation, we conducted a systematic review to summarize and synthesize the current literature. Electronic databases were systematically searched for prospective, longitudinal studies that examined risk factors of subsequent BPD outcomes (features, symptoms, diagnosis) resulting in a total of 39 studies, reflecting 24 unique samples. Though increased risk for BPD was reliably attributed to multiple factors within social, family, maltreatment, and child domains, the most striking limitation of this research is its lack of disorder-specific findings Additional limitations, including notable heterogeneity in sampling methodology, symptom assessment methodology, and developmental timing of assessments, are discussed in terms of how close are we to pinpointing who is most at risk and why in an attempt to provide a roadmap for future research.

Callous-unemotional (CU) traits have been shown to delineate a subgroup of individuals at high risk for exhibiting severe and persistent criminal behavior. The Inventory of Callous-Unemotional Traits (ICU; Frick 2004) was recently developed as a comprehensive rating scale designed to measure multiple facets of CU traits. However, validation of this measure has been limited to youth in adolescence and emerging adulthood (age range=12–20), leaving questions about the utility of this measure in early adulthood unanswered. The current study evaluated the factor structure of the ICU within a racially diverse and well characterized community sample of adult males (n=425) using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). While results found the best fitting model to be the three-bifactor structure that has been previously reported in adolescent samples, the fit indices were only marginally acceptable and suggest the need for scale refinement. Total and subscales scores demonstrated significant and distinct associations with relevant external criteria (e.g., delinquency, psychopathy, psychopathology, psychosocial functioning). Implications and directions for future research are discussed.