The study examined whether reciprocal friendship quantity or quality can mitigate genetic vulnerability for depression symptoms in children. The sample comprised 168 monozygotic twin pairs and 126 same-sex dizygotic twin pairs assessed in Grade 4 (mean age = 10.04 years). Friendship participation was measured via reciprocal nominations of close friendships within the classroom. Friendship quality was measured through self-reports. Depression symptoms were measured through teacher and peer reports. Genetic vulnerability for depression symptoms was unrelated to friendship participation or the number of reciprocal friends, but it was negatively related to positive friendship quality. In line with gene–environment interaction, genetic risk effects on depression symptoms were mitigated in girls who had at least one close reciprocal friend. In boys, only moderate main effects of genetic vulnerability and friendship participation were found but no interaction between them. However, among boys with at least one reciprocal friend, a greater number of friends was related to fewer depression symptoms whereas no cumulative effect of friendship was found for girls. Finally, positive friendship quality was related to fewer depression symptoms in girls and boys even when controlling for genetic risk. The findings emphasize the importance of teaching social interactional skills that promote high-quality friendship relations to help prevent the development of depression symptoms in children.

Early-life stress, such as maltreatment, institutionalization, and exposure to violence, is associated with accelerated telomere shortening. Telomere shortening may thus represent a biomarker of early adversity. Previous studies have suggested that responsive parenting may protect children from the negative biological and behavioral consequences of early adversity. This study examined the role of parental responsiveness in buffering children from telomere shortening following experiences of early-life stress. We found that high-risk children had significantly shorter telomeres than low-risk children, controlling for household income, birth weight, gender, and minority status. Further, parental responsiveness moderated the association between risk and telomere length, with more responsive parenting associated with longer telomeres only among high-risk children. These findings suggest that responsive parenting may have protective benefits on telomere shortening for young children exposed to early-life stress. Therefore, this study has important implications for early parenting interventions.

Little is known about the long-term neural consequences of adverse life events for healthy adolescents, and this is particularly the case for events that occur after a putative stress-sensitive period in early childhood. In this functional magnetic resonance imaging study of healthy adolescents, we found that prior exposure to severe adverse life events was associated with current anxiety and with increased amygdala reactivity to standardized emotional stimuli (viewing of fearful faces relative to calm ones). Conjunction analyses identified multiple regions, including the amygdala, insula, and prefrontal cortex, in which reactivity to emotional faces covaried with life events as well as with current anxiety. Our morphometric analyses suggest systemic alterations in structural brain development with an association between anxiety symptoms and global gray matter volume. No life events were reported for the period before 4 years of age, suggesting that these results were not driven by exposure to stress during an early sensitive period in development. Overall, these data suggest systemic effects of traumatic events on the dynamically developing brain that are present even in a nonclinical sample of adolescents.

Modern research acknowledges that psychopathology and individual differences in normal development are the joint products of both biological and social influences. Although there have been numerous publications on Gene × Environment interactions in the past decade, gene–environment correlation is another important form of gene–environment interplay that has received less attention. This Special Section demonstrates, using a range of methodological approaches, the importance of gene–environment correlation in developmental psychopathology. Several types of gene–environment correlation are described, including passive, evocative, and active. Other studies highlight the potential for gene–environment correlation to obscure associations between risk exposures and child psychopathology. Future directions for gene–environment correlation research are discussed.

Although children's active role in socialization has been long acknowledged, relevant research has typically focused on children's difficult temperament or negative behaviors that elicit coercive and adversarial processes, largely overlooking their capacity to act as positive, willing, even enthusiastic, active socialization agents. We studied the willing, receptive stance toward their mothers in a low-income sample of 186 children who were 24 to 44 months old. Confirmatory factor analysis supported a latent construct of willing stance, manifested as children's responsiveness to mothers in naturalistic interactions, responsive imitation in teaching contexts, and committed compliance with maternal prohibitions, all observed in the laboratory. Structural equation modeling analyses confirmed that ecological adversity undermined maternal responsiveness, and responsiveness, in turn, was linked to children's willing stance. A compromised willing stance predicted externalizing behavior problems, assessed 10 months later, and fully mediated the links between maternal responsiveness and those outcomes. Ecological adversity had a direct, unmediated effect on internalizing behavior problems. Considering children's active role as willing, receptive agents capable of embracing parental influence can lead to a more complete understanding of detrimental mechanisms that link ecological adversity with antisocial developmental pathways. It can also inform research on the normative socialization process, consistent with the objectives of developmental psychopathology.

Developmental psychopathology is described as a conceptual approach that involves a set of research methods that capitalize on developmental and psychopathological variations to ask questions about mechanisms and processes. Achievements are described in relation to attachment and attachment disorders, autism, schizophrenia, childhood antecedents of adult psychopathology, testing for environmental mediation of risk effects, gene–environment interplay, intellectual and language functioning, effects of mentally ill parents on the children, stress and vulnerability to depression, ethnicity and schizophrenia, and drug response. Continuities and discontinuities over the course of development are discussed in relation to attention-deficit/hyperactivity disorder, antisocial behavior, eating disorders, substance abuse and dependency, pharmacological and behavioral addictions, and a range of other disorders. Research challenges are considered in relation to spectrum concepts, the adolescent development of a female preponderance for depression, the mechanisms involved in age differences in response to drugs and to lateralized brain injury, the processing of experiences, the biological embedding of experiences, individual differences in response to environmental hazards, nature–nurture integration, and brain plasticity.

Preliminary work indicates that cognitive vulnerability to depression may be associated with variants of the serotonin transporter promoter polymorphism (5-HTTLPR) and the valine to methionine at position 66 (val66met) polymorphism of the brain-derived neurotrophic factor (BDNF) gene; however, existing reports come from small samples. The present study sought to replicate and extend this research in a sample of 375 community-dwelling children and their parents. Following a negative mood induction, children completed a self-referent encoding task tapping memory for positive and negative self-descriptive traits. Consistent with previous work, we found that children with at least one short variant of the 5-HTTLPR had enhanced memory for negative self-descriptive traits. The BDNF val66met polymorphism had no main effect but was moderated by maternal depression, such that children with a BDNF methionine allele had a heightened memory for negative self-descriptive traits when mothers had experienced depression during children's lifetimes; in contrast, children with a methionine allele had low recall of negative traits when mothers had no depression history. The findings provide further support for the notion that the 5-HTTLPR is associated with cognitive markers of depression vulnerability and that the BDNF methionine allele moderates children's sensitivity to contextual factors.

Evidence suggests that the 7-repeat variant of a 48 base pair variable number tandem repeat polymorphism in the dopamine receptor D4 (DRD4) gene may be associated with the development of attention problems. A parallel literature suggests that genes linked to dopaminergic functioning may be associated with differential sensitivity to context, such that the direction of the genetic effect is hypothesized to vary across environmental experience. Guided by these literatures, we used data from the NICHD Study of Early Child Care and Youth Development to consider (a) whether individual differences in children's inattention problems across middle childhood are predicted by gene–environment interactions between the DRD4 gene 7-repeat polymorphism and children's experiences of maternal sensitivity across infancy and early childhood and (b) the degree to which such interactions are consistent with the differential-sensitivity model. Largely consistent with the hypothesized model, gene–environment interactions indicated that, in the context of insensitive early maternal care, the DRD4 7-repeat polymorphism was associated with higher levels of inattention. Although somewhat less consistently, there was also evidence that, in the context of highly sensitive care, the 7-repeat polymorphism was associated with lower levels of inattention. Overall, the magnitude of the absolute genetic effect increased over time, as children's inattention trajectories diverged.

Gene–environment correlation (rGE) exists both within and between families. Between families, accumulating rGE has been used to explain dramatic changes in phenotypic means over time. The Dickens and Flynn model of increases in cognitive ability over generational time, for example, suggests that small changes in phenotype can lead to subsequent reallocation of environmental resources. This process sets up a reciprocal feedback loop between phenotype and environment, producing accumulating rGE that can cause large changes in the mean of ability, even though ability remains highly heritable in cross-sectional data. We report simulations suggesting that similar processes may operate within twin and sibling pairs. Especially in dizygotic twins and siblings, small differences in phenotype can become associated with reallocations of environmental resources within families. We show that phenotype–environment effects can account for age-related increases in rGE, rapid differentiation of siblings raised together, and widely reported increases in the heritability of behavior during childhood and adolescence.

Child maltreatment, peer victimization, and a polymorphism of the serotonin transporter gene (5-HTTLPR) were examined as predictors of depressive symptomatology. Children (M age = 11.26, SD = 1.65), including 156 maltreated and 145 nonmaltreated children from comparable low socioeconomic backgrounds, provided DNA samples and self-reports of relational peer victimization, overt peer victimization, and depressive symptoms. Path analysis showed that relational and overt victimization mediated the association between child maltreatment and depressive symptoms. Bootstrapping procedures were used to test moderated mediation and demonstrated that genotype moderated the indirect effects of relational and overt victimization on child depressive symptoms, such that victimized children with the long/long variation were at an increased risk for depressive symptoms compared to victimized children carrying a short allele. Results highlight the utility of examining process models that incorporate biological and psychological factors contributing to the development of depressive symptomatology and provide direction toward understanding and promoting resilience among high-risk youth from a multiple levels of analysis approach.

Using the Durham Child Health and Development Study, this study (N = 171) tested whether observed parenting behaviors in infancy (6 and 12 months) and toddlerhood/preschool (24 and 36 months) interacted with a child polymorphism of the brain-derived neurotrophic factor gene to predict oppositional defiant disorder (ODD) and callous–unemotional (CU) behaviors at age 3 years. Child genotype interacted with observed harsh and intrusive (but not sensitive) parenting to predict ODD and CU behaviors. Harsh–intrusive parenting was more strongly associated with ODD and CU for children with a methionine allele of the brain-derived neurotrophic factor gene. CU behaviors were uniquely predicted by harsh–intrusive parenting in infancy, whereas ODD behaviors were predicted by harsh–intrusive parenting in both infancy and toddlerhood/preschool. The results are discussed from the perspective of the contributions of caregiving behaviors as contributing to distinct aspects of early onset disruptive behavior.

Progress in the field of developmental psychopathology is appraised in general and with regard to the particular lens of our understanding of the development of disorder. In general, the outpouring of research on various features of disorder and underlying processes could not have even been imagined 25 years ago. The progress is dazzling. At the same time, work on the development of disorders, beginning with antecedent patterns of adaptation, pales in comparison with work on the correlates of disorder. However, progress has been made. It is well established that the brain develops in the context of experience and that organism and environment continually interact over time. Something is now known about pathways leading to certain disorders and what initiates and impels individuals along them. If developmental psychopathology is to completely fulfill its promise of offering new ways of conceptualizing disorder and new guidance for prevention and intervention, much more work on developmental processes and a new way of exploring the development of disorder will be needed. Such a path is suggested.

Teenage childbirth is a risk factor for poor offspring outcomes, particularly offspring antisocial behavior. It is not clear, however, if maternal age at first birth (MAFB) is causally associated with offspring antisocial behavior or if this association is due to selection factors that influence both the likelihood that a young woman gives birth early and that her offspring engage in antisocial behavior. The current study addresses the limitations of previous research by using longitudinal data from Swedish national registries and children of siblings and children of twins comparisons to identify the extent to which the association between MAFB and offspring criminal convictions is consistent with a causal influence and confounded by genetic or environmental factors that make cousins similar. We found offspring born to mothers who began childbearing earlier were more likely to be convicted of a crime than offspring born to mothers who delayed childbearing. The results from comparisons of differentially exposed cousins, especially born to discordant monozygotic twin sisters, provide support for a causal association between MAFB and offspring criminal convictions. The analyses also found little evidence for genetic confounding due to passive gene–environment correlation. Future studies are needed to replicate these findings and to identify environmental risk factors that mediate this causal association.

This cross-sectional study seeks to (a) describe developmental correlates of sensory hyporesponsiveness to social and nonsocial stimuli, (b) determine whether hyporesponsiveness is generalized across contexts in children with autism relative to controls, and (c) test the associations between hyporesponsiveness and social communication outcomes. Three groups of children ages 11–105 months (N = 178; autism = 63, developmental delay = 47, typical development = 68) are given developmental and sensory measures including a behavioral orienting task (the Sensory Processing Assessment). Lab measures are significantly correlated with parental reports of sensory hyporesponsiveness. Censored regression models show that hyporesponsiveness decreased across groups with increasing mental age (MA). Group differences are significant but depend upon two-way interactions with MA and context (social and nonsocial). At a very young MA (e.g., 6 months), the autism group demonstrates more hyporesponsiveness to social and nonsocial stimuli (with larger effects for social) than developmental delay and typically developing groups, but at an older MA (e.g., 60 months) there are no significant differences. Hyporesponsiveness to social and nonsocial stimuli predicts lower levels of joint attention and language in children with autism. Generalized processes in attention disengagement and behavioral orienting may have relevance for identifying early risk factors of autism and for facilitating learning across contexts to support the development of joint attention and language.

Parental depression is associated with disruptions in the parent–child relationship, exposure to stressful family life events, and offspring depressive symptoms. Evidence suggests that intergenerational transmission of depression involves environmental and inherited contributions. We sought to evaluate the role of passive gene–environment correlation (rGE) in relation to depression, family life events that were due to parental behavior, and parental positivity in a sample where children varied in genetic relatedness to their rearing parents. Our study included 865 families with children born through assisted conception (444 related to both parents, 210 related to the mother only, 175 related to the father only, and 36 related to neither parent). Consistent with previous studies, the intergenerational transmission of depressive symptoms was largely due to environmental factors, although parent and child gender influenced results. Maternal and paternal depressive symptoms were associated with reduced positivity and increased parentally imposed life events regardless of parent–child relatedness. Results of path analysis were consistent with passive rGE for both maternal and paternal positivity in that positivity partially mediated the link between maternal/paternal depression and child depression only in genetically related parent–child pairs. Results also suggested passive rGE involving parentally imposed life events for mothers and fathers although passive rGE effects were smaller than for positivity.

Although relations between political violence and child adjustment are well documented, longitudinal research is needed to adequately address the many questions remaining about the contexts and developmental trajectories underlying the effects on children in areas of political violence. The study examined the relations between sectarian and nonsectarian community violence and adolescent adjustment problems over 4 consecutive years. Participants included 999 mother–child dyads (482 boys, 517 girls), M ages = 12.18 (SD = 1.82), 13.24 (SD = 1.83), 13.61 (SD = 1.99), and 14.66 (SD = 1.96) years, respectively, living in socially deprived neighborhoods in Belfast, Northern Ireland, a context of historical and ongoing political violence. In examining trajectories of adjustment problems, including youth experience with both sectarian and nonsectarian antisocial behaviors, sectarian antisocial behavior significantly predicted more adjustment problems across the 4 years of the study. Experiencing sectarian antisocial behavior was related to increased adolescent adjustment problems, and this relationship was accentuated in neighborhoods characterized by higher crime rates. The discussion considers the implications for further validating the distinction between sectarian and nonsectarian violence, including consideration of neighborhood crime levels, from the child's perspective in a setting of political violence.

The present study examined the specificity of autobiographical memory in adolescents and adults with versus without child sexual abuse (CSA) histories. Eighty-five participants, approximately half of whom per age group had experienced CSA, were tested on the Autobiographical Memory Interview. Individual difference measures, including those for trauma-related psychopathology, were also administered. Findings revealed developmental differences in the relation between autobiographical memory specificity and CSA. Even with depression statistically controlled, reduced memory specificity in CSA victims relative to controls was observed among adolescents but not among adults. A higher number of posttraumatic stress disorder criteria met predicted more specific childhood memories in participants who reported CSA as their most traumatic life event. These findings contribute to the scientific understanding of childhood trauma and autobiographical memory functioning and underscore the importance of considering the role of age and degree of traumatization within the study of autobiographical memory.

Thirteen-month-old maltreated infants (n = 137) and their mothers were randomly assigned to one of three conditions: child–parent psychotherapy (CPP), psychoeducational parenting intervention (PPI), or community standard (CS). A fourth group of nonmaltreated infants (n = 52) and their mothers served as a nonmaltreated comparison (NC) group. A prior investigation found that the CPP and the PPI groups demonstrated substantial increases in secure attachment at postintervention, whereas this change was not found in the CS and the NC groups. The current investigation involved the analysis of data obtained at a follow-up assessment that occurred 12 months after the completion of treatment. At follow-up, children in the CPP group had higher rates of secure and lower rates of disorganized attachment than did children in the PPI or the CS group. Rates of disorganized attachment did not differ between the CPP and the NC groups. Intention to treat analyses also showed higher rates of secure attachment at follow-up in the CPP group relative to the PPI and the CS groups. However, groups did not differ on disorganized attachment. Both primary and intention to treat analyses demonstrated that maternal-reported child behavior problems did not differ among the four groups at the follow-up assessment. This is the first investigation to demonstrate sustained attachment security in maltreated children 12 months after the completion of an attachment theory informed intervention. The findings also suggest that, although effective in the short term, parenting interventions alone may not be effective in maintaining secure attachment in children over time.

The disciplines of developmental psychopathology and behavior genetics are concerned with many of the same questions about the etiology and course of normal and abnormal behavior and about the factors that promote typical development despite the presence of risk. The goal of this paper is to summarize how research in behavior genetics has shed light on questions that are central to developmental psychopathology. We briefly review the origins of behavior genetics, summarize the findings that have been gleaned from several decades of quantitative and molecular genetics research, and describe future directions for research that will delineate gene function as well as pathways from genes to brain to behavior. The importance of environmental contributions, at both genetic and epigenetic levels, will be discussed. We conclude that behavior genetics has made significant contributions to developmental psychopathology by documenting the interplay among risk and protective factors at multiple levels of the organism, by clarifying the causal status of risk exposures, and by identifying factors that account for change and stability in psychopathology. As the tools to identify gene function become increasingly sophisticated, and as behavioral geneticists become increasingly interdisciplinary in their scope, the field is poised to make ever greater contributions to our understanding of typical and atypical development.