Research Review: genetic vulnerability or differential susceptibility in child development: the case of attachment

From temperament and parenting to attachment: a review of the interplay of gene and environment factors in the developmental pathway to attachment

PURPOSE OF REVIEW

Attachment represents an aspect of the parent-child relationship by encapsulating behaviours and stress management strategies. Although attachment is not considered a measure of psychopathology, some attachment styles place children at higher risk for psychopathologies. The origins of attachment have historically thought to be either parenting-related variables, or temperament. More recently, there has been accumulated evidence of gene × environment interactions in attachment, temperament, and parenting. This review aims to cover shared gene × environment pathways between these variables, introduce recent relevant insights from prenatal programming research, and offer a synthesized developmental cascade model of attachment.

RECENT FINDINGS

Carriers of gene polymorphisms related to stress neurobiology respond differently to environments than noncarriers according to two patterns: attachment research shows inconsistent diathesis-stress between gene polymorphisms and environment, and temperament, stress physiology, and prenatal programming research show clear patterns of differential susceptibility.

SUMMARY

By synthesizing prenatal and postnatal findings, a model of attachment emerges in which individuals more susceptible to environmental influences are carriers of specific genes, whose endophenotypic markers include stress biology and phenotypic markers include temperament. Intervention should, therefore, focus on parenting and stress regulation strategies for these individuals.

Concepts travel faster than thought: an empirical study of the use of attachment classifications in child protection investigations

Scholarly discussion suggests prevalent, overconfident use of attachment classifications in child protection (CP) investigations but no systematic research has examined actual prevalence, the methods used to derive such classifications, or their interpretations. We aimed to cover this gap using survey data from a nationally representative sample of Swedish CP workers (N = 191). Three key findings emerged. First, the vast majority formed an opinion about young children's attachment quality in all or most investigations. Second, most did not employ systematic assessments, and none employed well-validated attachment methods. Third, there was overconfidence in the perceived implications of attachment classifications. For example, many believed that insecure attachment is a valid indicator of insufficient care. Our findings illustrate a wide researcher-practitioner gap. This gap is presumably due to inherent difficulties translating group-based research to the level of the individual, poor dissemination of attachment theory and research, and infrastructural pressures adversely influencing the quality of CP investigations.

Quo Vadis Psychiatry? Why It Is Time to Endorse Evolutionary Theory

In recent decades, psychiatry and the neurosciences have made little progress in terms of preventing, diagnosing, classifying, or treating mental disorders. Here we argue that the dilemma of psychiatry and the neurosciences is, in part, based on fundamental misconceptions about the human mind, including misdirected nature-nurture debates, the lack of definitional concepts of "normalcy," distinguishing defense from defect, disregarding life history theory, evolutionarily uninformed genetic and epigenetic research, the "disconnection" of the brain from the rest of the body, and lack of attention to actual behavior in real-world interactions. All these conceptual difficulties could potentially benefit from an approach that uses evolutionary theory to improve the understanding of causal mechanisms, gene-environment interaction, individual differences in behavioral ecology, interaction between the gut (and other organs) and the brain, as well as cross-cultural and across-species comparison. To foster this development would require reform of the curricula of medical schools.

Childhood Maltreatment, Automatic Negative Thoughts, and Resilience: The Protective Roles of Culture and Genes

Resilience, a psychological trait conceptualized as the ability to recover from setbacks, can be weakened by childhood maltreatment, which comprises childhood abuse and childhood neglect. The current study aimed to investigate whether childhood maltreatment could increase automatic negative thoughts (ANT), thus weakening resilience. Furthermore, as psychological characteristics are commonly subject to the moderating effects of cultural context and biology, the study also explored whether and how cultural and genetic factors separately interact with childhood maltreatment to predict resilience. In study 1, the participants comprised 237 American and 347 Chinese individuals; study 2 included 428 genotyped Chinese individuals. We combined regression, mediation, moderation, and machine learning methods to test the mediating effect of ANT on the link between childhood maltreatment and resilience as well as the moderating roles of culture and genetics. Study 1 found that both childhood abuse and childhood neglect increased ANT and thus weakened resilience. In addition, the ANT-mediating effects of childhood neglect were stronger in American than Chinese participants. In Study 2, using the leave-one-out approach, we constructed two separate prediction models based on 22 and 16 important single nucleotide polymorphisms (SNPs), and we found that the interaction between childhood abuse/neglect and polygenic scores based on important SNPs could predict ANT. The mediating effects of ANT on the relationship between childhood abuse/neglect and resilience were significant for participants with low polygenic scores but not for those with high polygenic scores. In conclusion, both the cultural environment and individual genetic makeup moderated the mediating effects of ANT on the association between childhood maltreatment and resilience. These findings indicated the roles of culture and genetics in protecting against the adverse effects of childhood maltreatment on resilience.

How to Support Parents of Infants and Young Children in Mental Health Care: A Narrative Review

Objective: The aim of this narrative review is to gain insight into the appropriate intervention targets when parents of infants and young children suffer from psychopathology. Background: Psychopathology in parents is a risk factor for maladaptive parenting and is strongly related to negative cascade effects on parent-child interactions and relations in the short and long term. Children in their first years of life are especially at risk. However, in adult mental health care, this knowledge is rarely translated into practice, which is a missed opportunity for prevention. Methods: Electronic databases were searched for reviews and meta-analysis. In addition, sources were obtained via manual search, reference mining, expert opinion, and communications from conferences. In total, 56 papers, whereof 23 reviews and 12 meta-analyses were included. Results: Findings regarding targets of intervention were identified in different interacting domains, namely the parental, family, child, and environmental domains as well as the developing parent-child relationship. A "one size fits all" intervention is not appropriate. A flexible, tailored, resource-oriented intervention program, multi-faceted in addressing all modifiable risk factors and using different methods (individual, dyadic, group), seems to provide the best results. Conclusion: To address the risk factors in different domains, adult and child mental health care providers should work together in close collaboration to treat the whole family including mental disorders, relational, and contextual problems. A multi-agency approach that includes social services is needed.

Physiological Factors Linking Insecure Attachment to Psychopathology: A Systematic Review

Although many studies have documented associations between insecure attachment and psychopathology, attachment may not confer risk for psychopathology independently, but rather through its interaction with emotional, social, and biological factors. Understanding the variables through which attachment may lead to psychopathology is therefore important. Within this domain of research, the role of physiological factors is poorly investigated. What are the relevant domains and why, when, or for whom do they influence mental disorders relating to attachment? The current systematic review aims to answer these questions. Results reveal that physiological indices of emotional regulation play a role in explaining and/or determining the relationship between attachment and psychopathology. Specifically: (1) combined with insecure attachment, higher skin conductance level (SCL), lower cardiac slowing, and respiratory sinus arrhythmia modulation (RSA) contribute to different psychopathological indicators and behavioral/psychological dysfunctions, although the latter predicts a contradictory pattern of findings; (2) insecure-avoidant attachment is more consistently linked with stress and emotional dysregulation when combined with RSA, while anxious attachment confers risk of depressive symptoms when combined with SCL. We concluded our discussion of the results of seven studies by outlining a plan to move the field forward. We discuss the quality of the assessment, methodological limitations, and future directions, highlighting the need to extend the research to clinical samples.

The peril and promise of sensitivity in eating disorders

Differential susceptibility, a reconceptualization of the diathesis-stress model of psychopathology, describes gene-environment interactions that reflect individual differences in responsiveness to environmental influences, both detrimental and beneficial. This model has been described metaphorically by the classification of orchids, which thrive under optimal care but wither under adverse conditions, and dandelions, which weather broad environmental circumstances but are less responsive to careful cultivation. Etiological research in the field of eating disorders has largely focused on the identification of specific behavioral phenotypes, temperamental traits, genotypes and neurobiological processes that confer risk. In this article, we propose that these putative vulnerability factors represent phenotypes and endophenotypes of a genetic predisposition towards environmental sensitivity. We assert that this sensitivity not only transmits eating disorder risk but also confers resilience, depending on the circumstances. In particular, we propose that differential susceptibility can be used as a framework to organize disparate temperamental and neurobiological findings and their complex interplay with various developmental, environmental and sociocultural influences to increase eating disorder risk and treatment responsiveness. Finally, we assert that viewed through the lens of differential susceptibility, sensitivity can be leveraged to refine our interventions and develop novel treatment and prevention strategies to support favorable outcomes for individuals with eating disorders.

The association between familial death in childhood or adolescence and subsequent substance use disorder: A systematic review and meta-analysis

BACKGROUND

Exposure to childhood adversity has been linked to long-term negative mental health consequences in adulthood.

PURPOSE

This review examined the association between exposure to the death of a family member (i.e., parent or sibling) during childhood or adolescence and the subsequent diagnosis of a substance use disorder.

METHODS

Electronic databases (Scopus, Medline (for Ovid), EMBASE, and PsychINFO) were searched for cohort and case-control studies in the English language. Studies were retained if it was demonstrable that exposure to death occurred before age 18, and that disorder was diagnosed subsequently. Sensitivity analyses were performed for the meta-analysis, and study quality assessed using the Newcastle-Ottawa Scale.

RESULTS

Nine studies, seven cohort and two case-control, were retained. Due to differential metrics (hazard ratios [HRs] versus odds/risk ratios [ORs/RRs]), only one meta-analysis was possible. Individuals experiencing familial death had 1.42 (95% CI = 0.96, 2.09) times the odds of developing a substance use disorder compared to those non-exposed. Where there was a statistically significant effect in other studies, these were mostly studies using National Registers (1.4 ≤ HR ≤ 2.51).

LIMITATIONS

Meta-analysis options were limited by the variety of study designs.

CONCLUSIONS

Evidence for a significant association between familial death and subsequent disorder appears to be an artefact of the study design. Implications of key findings. Further studies are required to better understand and estimate the association between familial death and substance use disorders. Registration and funding. The review was pre-registered (PROSPERO Reg No: CRD42020192892) and funded by the Irish Research Council (COALESCE/2019/61).

Associations Among Parental Caregiving Quality, Cannabinoid Receptor 1 Expression-Based Polygenic Scores, and Infant-Parent Attachment: Evidence for Differential Genetic Susceptibility?

Attachment is a biological evolutionary system contributing to infant survival. When primary caregivers/parents are sensitive and responsive to their infants’ needs, infants develop a sense of security. Secure infant attachment has been linked to healthy brain and organ-system development. Belsky and colleagues proposed the term differential susceptibility to describe context-dependent associations between genetic variations and behavioral outcomes as a function of parenting environments. Variations in the Cannabinoid Receptor Gene 1 (CNR1) are associated with memory, mood, and reward and connote differential susceptibility to more and less optimal parental caregiving quality in predicting children’s behavioral problems.

Exploring Perinatal Indicators of Infant Social-Emotional Development: A Review of the Replicated Evidence

The importance of infant social-emotional development for outcomes across the lifecourse has been amply demonstrated. Despite this, most screening measures of social-emotional development are designed for children 18 months of age and over, with a clear gap in earlier infancy. No systematic review has yet harvested the evidence for candidate indicators in the perinatal window. This paper examines modifiable risk and protective factors for two seminal early markers of social-emotional development: attachment security and behavioral regulation mid-infancy. We searched meta-analytic and longitudinal studies of developmental relationships between modifiable exposures in the perinatal window (pregnancy to 10 months postpartum) and attachment and behavioral regulation status measured between 12 and 18 months. Six electronic databases were used: ERIC, PsycINFO, Medline Complete, Informit, Embase, and Scopus. Twelve meta-analytic reviews and 38 original studies found replicated evidence for 12 indicators across infant, caregiving, and contextual domains predictive of infant behavioral regulation and attachment status between 12 and 18 months. Key among these were caregiving responsiveness, maternal mental health, couple relationship, and SES as a contextual factor. Perinatal factors most proximal to the infant had the strongest associations with social-emotional status. Beyond very low birthweight and medical risk, evidence for infant-specific factors was weaker. Risk and protective relationships were related but not always inverse. Findings from this review have the potential to inform the development of reliable tools for early screening of infant social-emotional development for application in primary care and population health contexts.

Genetic architecture of Environmental Sensitivity reflects multiple heritable components: a twin study with adolescents

Humans differ substantially in how strongly they respond to similar experiences. Theory suggests that such individual differences in susceptibility to environmental influences have a genetic basis. The present study investigated the genetic architecture of Environmental Sensitivity (ES) by estimating its heritability, exploring the presence of multiple heritable components and its genetic overlap with common personality traits. ES was measured with the Highly Sensitive Child (HSC) questionnaire and heritability estimates were obtained using classic twin design methodology in a sample of 2868 adolescent twins. Results indicate that the heritability of sensitivity was 0.47, and that the genetic influences underlying sensitivity to negative experiences are relatively distinct from sensitivity to more positive aspects of the environment, supporting a multi-dimensional genetic model of ES. The correlation between sensitivity, neuroticism and extraversion was largely explained by shared genetic influences, with differences between these traits mainly attributed to unique environmental influences operating on each trait.

Pathways to social-emotional functioning in the preschool period: The role of child temperament and maternal anxiety in boys and girls

Individual differences in social-emotional functioning emerge early and have long-term implications for developmental adaptation and competency. Research is needed that specifies multiple early risk factors and outcomes simultaneously to demonstrate specificity. Using multigroup longitudinal path analysis in a sample of typically developing children (N = 541), we examined child temperament dimensions (surgency, negative affectivity, and regulation/effortful control) and maternal anxiety in infancy and age 2 as predictors of child externalizing, internalizing, dysregulation, and competence behaviors at age 3. Four primary patterns emerged. First, there was stability in temperament dimensions and maternal anxiety from infancy to age 3. Second, negative affectivity was implicated in internalizing problems and surgency in externalizing problems. Third, effortful control at age 2 was a potent mediator of maternal anxiety in infancy on age 3 outcomes. Fourth, there was suggestive evidence for transactional effects between maternal anxiety and child effortful control. Most pathways operated similarly for boys and girls, with some differences, particularly for surgency. These findings expand our understanding of the roles of specific temperamental domains and postnatal maternal anxiety in a range of social-emotional outcomes in the preschool period, and have implications for efforts to enhance the development of young children's social-emotional functioning and reduce risk for later psychopathology.

The building blocks of social competence: Contributions of the Consortium of Individual Development

Social competence refers to the ability to engage in meaningful interactions with others. It is a crucial skill potentially malleable to interventions. Nevertheless, it remains difficult to select which children, which periods in a child's life, and which underlying skills form optimal targets for interventions. Development of social competence is complex to characterize because (a) it is by nature context- dependent; (b) it is subserved by multiple relevant processes that develop at different times in a child's life; and (c) over the years multiple, possibly conflicting, ways have been coined to index a child's social competence. The current paper elaborates upon a theoretical model of social competence developed by Rose-Krasnor (Rose- Krasnor, 1997; Rose-Krasnor and Denham, 2009), and it makes concrete how underlying skills and the variety of contexts of social interaction are both relevant dimensions of social competence that might change over development. It then illustrates how the cohorts and work packages in the Consortium on Individual Development each provide empirical contributions necessary for testing this model on the development of social competence.

Serotonergic sensitivity alleles moderate relations between attachment security at age three and socioemotional competence at age five

Children with higher socioemotional competence are more likely to build constructive relationships with others and experience more positive adjustment outcomes in later periods. Securely attached children are likely to develop better socioemotional competence, but genetic moderation of associations between attachment and later socioemotional competence has received less attention. Using structural equation modeling, this study analyzed data collected from 1,337 children (51% male) born from 1998 to 2000 in the Fragile Families and Child Wellbeing study. The results demonstrated that relations between attachment security at age 3 years and their social competence at age 5 years differed by two serotonin transporter variants (5-HTTLPR, STin2). Effect sizes of these interactions were larger than effect sizes of main effects and the benefit of having sensitive alleles was consistently supported. This implies that having more secure attachment in the early developmental period is advantageous especially for children with minor alleles who have greater environmental sensitivity.

Catechol-O-methyltransferase Val158Met Genotype and Early-Life Family Adversity Interactively Affect Attention-Deficit Hyperactivity Symptoms Across Childhood

Attention-deficit hyperactivity disorder (ADHD) is among the most commonly diagnosed psychiatric disorders of childhood. The dopaminergic system has been shown to have substantial effects on its etiology, with both functional Catechol-O-methyltransferase (COMT) Val158Met genotype and early-life environmental adversity involved in the risk of inattention and hyperactivity/impulsivity symptoms. In this prospective longitudinal study, we examined for the first time the impact of proximal and distal early-life family adversity and COMT Val158Met polymorphism gene - both the direct and the interactive effects, on children's ADHD symptoms across childhood. Data came from the Family Life Project, a prospective longitudinal study of 1,292 children and families in high poverty from birth to 11 years. In infancy, data regarding socioeconomic (SES)-risk-factors, observed-caregiving behaviors, and DNA genotyping were collected. In early and middle childhood teachers rated the occurrence and severity of the child's ADHD symptoms. Multilevel growth curve models revealed independent effects of COMT, early-life SES-risk and negative caregiving on ADHD symptoms in early and middle childhood. Significant gene-environment interactions were found, indicating that overall, carriers of at least one COMT158Met allele were more sensitive to early-life adversity, showing higher inattention and hyperactivity/impulsivity symptoms severity in childhood when exposed to high SES-risk factors in infancy, compared to Val-Val carriers. Findings provide new insights into the complex etiology of ADHD and underline the need for further investigation of the neuronal mechanisms underlying gene-environment interactions. Findings might have implications for prevention and intervention strategies with a focus on early-life family relationships in genetically at-risk children.

Predicted DRD4 prefrontal gene expression moderates snack intake and stress perception in response to the environment in adolescents

Body weight is substantially determined by eating behaviors, which are themselves driven by biological factors interacting with the environment. Previous studies in young children suggest that genetic influences on dopamine function may confer differential susceptibility to the environment in such a way that increases behavioral obesity risk in a lower socioeconomic status (SES) environment but decreases it in a higher SES environment. We aimed to test if this pattern of effect could also be observed in adolescence, another critical period for development in brain and behavior, using a novel measure of predicted expression of the dopamine receptor 4 (DRD4) gene in prefrontal cortex. In a sample of 76 adolescents (37 boys and 39 girls from Baltimore, Maryland/US, aged 14-18y), we estimated individual levels of DRD4 gene expression (PredDRD4) in prefrontal cortex from individual genomic data using PrediXcan, and tested interactions with a composite SES score derived from their annual household income, maternal education, food insecurity, perceived resource availability, and receipt of public assistance. Primary outcomes were snack intake during a multi-item ad libitum meal test, and food-related impulsivity assessed using a food-adapted go/no-go task. A linear regression model adjusted for sex, BMI z-score, and genetic ethnicity demonstrated a PredDRD4 by composite SES score interaction for snack intake (p = 0.009), such that adolescents who had lower PredDRD4 levels exhibited greater snack intake in the lower SES group, but lesser snack intake in the higher SES group. Exploratory analysis revealed a similar pattern for scores on the Perceived Stress Scale (p = 0.001) such that the low PredDRD4 group reported higher stress in the lower SES group, but less stress in the higher SES group, suggesting that PredDRD4 may act in part by affecting perceptions of the environment. These results are consistent with a differential susceptibility model in which genes influencing environmental responsiveness interact with environments varying in obesogenicity to confer behavioral obesity risk in a less favorable environment, but behavioral obesity protection in a favorable one.

Disentangling genes, attachment, and environment: A systematic review of the developmental psychopathology literature on gene-environment interactions and attachment

The role of genetics in relation to attachment is of continued interest to developmental psychology. Recent research has attempted to disentangle genetic main effects, environmental effects, and gene and environment (G × E) interactions in the development of attachment security/insecurity and disorganization. We systematically reviewed associations between gene markers and attachment, including G × E interactions, identifying 27 eligible studies. Inconsistent results emerged for associations between both gene effects and G × E interactions on attachment organization. Where G × E interactions used attachment as the environmental factor in the interaction, we observed more consistent results for differential susceptibility of G × E interactions on offspring behavior. Small sample size and heterogeneity in measurement of environmental factors impacted on comparability of studies. From these results, we propose that the future of research into the role of genetic effects in attachment lies in further exploration of G × E interactions, particularly where attachment acts as an environmental factor impacting on other child developmental outcomes emerging from the caregiving environment, consistent with differential susceptibility approaches to developmental psychopathology. In addition, from a methodological perspective, establishing the role of gene markers in such models will require a shift toward contemporary genomics, including genome-wide analysis (including novel genes and chromosomal loci), and epigenetic individual variations.

Genes and environment in attachment

In the last two decades, there has been increasing research interest in disentangling the contribution of genetic and environmental factors to individual differences in attachment, and in identifying the genes involved in shaping attachment. Twin studies suggest that as attachment changes during the course of development, genetic factors may play a progressively more important role, while shared environmental effects might decrease. However, most of this literature is limited by low power, measurement issues, and cross-sectional design. The findings of molecular genetic studies are, overall, inconclusive. The literature on main genetic effects and gene-by-environment interactions on attachment is filled with inconsistent and unreplicated findings. Also, most studies are underpowered. Challenges for future research are to identify the unshared environmental mechanisms involved in shaping attachment, and to better elucidate the genes involved and their interaction with the environment. Some pioneer studies suggested that the incorporation of epigenetic processes into G × E interaction models might represent a promising future way for investigating the complex, dynamic interplay between genes, environment, and attachment.

Attachment, culture, and gene-culture co-evolution: expanding the evolutionary toolbox of attachment theory

I argue that attachment relationships, and particularly secure ones, are important contexts for social learning and cultural transmission. Bowlby originally treated the attachment-behavioral system as serving only one evolutionary function: protection, via physical proximity. Yet the time is ripe to consider learning, especially social learning, as an additional functional consequence of attachment. Updated accordingly, attachment theory has the potential to serve as a much-needed developmental anchor for models of cultural evolution and gene-culture co-evolution. To support my arguments, I review progress in evolutionary science since Bowlby's lifetime, highlighting the growing recognition of ecological flexibility and the cultural embeddedness of animal behavior. I also review research pointing to a facilitating role of secure attachment relationships for social learning from caregivers among humans. For illustrational purposes, I show how one important aspect of human culture - religion - is culturally transmitted within attachment relationships, and of how the generalization of attachment-related working models biases the cultural transmission of religion from parents to offspring. I end the paper with a call for empirical research to test the role of attachment in cultural transmission beyond religion.

Associations of multiple trauma types and MAOA with severe aggressive behavior and MAOA effects on training outcome

Previous research showed that the disposition to react with disproportionate aggression in adults is influenced by an interaction between a variant in the X-chromosomal monoamine oxidase A gene (MAOA) and early traumatic events. Such studies have often focused on a single type of trauma, whereas we know that experiencing multiple trauma types is associated with more detrimental consequences. The differential susceptibility hypothesis suggests that individuals who are most susceptible to adversity, are also most likely to benefit from supportive experiences in childhood. Differences in susceptibility are thought to be partly genetically driven. In the present study we explored whether a genotype of MAOA linked to lower expression of the gene (MAOA-L) modified the effect of multiple types of trauma on aggression and/or altered responsiveness to treatment among adults with severe aggression. Forensic psychiatric outpatients (FPOs) (N=150) receiving treatment for aggression regulation problems were recruited. Traumatic events and aggression were measured using self-report. FPOs with multiple trauma types and those with the MAOA-L allele reported more severe levels of aggression. No interaction effects between MAOA genotype and trauma emerged. There were no differences in response to the intervention between FPOs with and without the MAOA-L variant, whereas FPOs with a single type of trauma showed the slowest reduction of aggression. FPOs with multiple types of trauma reported the highest levels of aggression over the course of treatment. Future research is needed to elucidate this association in further detail. The current study emphasized the importance of early recognition of early traumatic events.

Maternal Personality and Child Temperamental Reactivity: Differential Susceptibility for Child Externalizing Behavioral Problems in China

It is important to identify the developmental antecedents of externalizing behavioral problems in early childhood. The current study examined the main effects of maternal personality and its interactive effects with child temperamental reactivity in predicting child externalizing behavioral problems, indicated by impulsivity and aggression. This study was composed of 70 children (M _age = 17.6 months, SD = 3.73) and their mothers. The results showed that maternal agreeableness was negatively associated with child impulsivity. Child temperamental reactivity moderated the effect of maternal conscientiousness on child impulsivity in support of the differential susceptibility model. Specifically, for highly reactive children, maternal conscientiousness was negatively associated with child impulsivity whereas this association was non-significant for low reactive children. Child reactivity also moderated the contribution of maternal neuroticism to child impulsivity. That is, maternal neuroticism was negatively associated with impulsivity, only for highly reactive children.

Oxytocin receptor gene (OXTR) variant rs1042778 moderates the influence of family environment on changes in perceived social support over time

BACKGROUND

Lack of social support is an established risk factor across health outcomes, making it important to examine its family environmental and genetic determinants.

METHODS

In a 27-year follow-up of the Young Finns Study (N = 2341), we examined with a latent growth curve model whether genes involved in the oxytocin signaling pathway-namely, oxytocin receptor gene (OXTR) variants rs1042778, rs2254298, and rs53576-moderate the effect of early-life social experiences on perceived social support across the life span. Mothers reported the emotional warmth and acceptance towards their children at baseline when the participants were from 3 to 18 years old (1980). Perceived family support and support from friends and peripheral sources were assessed in five follow-ups 18 years apart (1989-2007).

RESULTS

Maternal emotional warmth and acceptance predicted the initial level of perceived social support across subscales, while the rate of change in family support was affected by the family environment only if participants carried the T-allele of OXTR rs1042778. This gene-environment interaction was not found for the rate of change in support from friends and peripheral sources and we also did not find associations between latent growth in perceived social support and OXTR variants rs53576 and rs2254298.

LIMITATIONS

Selective attrition in perceived social support, maternal emotional warmth and acceptance, gender, and SES. Family environment was assessed by a non-standardized measure.

CONCLUSIONS

OXTR rs1042778 polymorphism seems to contribute to changes in perceived family support in that way that some individuals (T-allele carriers) 'recover', to some extent, from the effects of early-life social experiences, whereas others (G/G genotype carriers) do not.

Distinctive heritability patterns of subcortical-prefrontal cortex resting state connectivity in childhood: A twin study

Connectivity between limbic/subcortical and prefrontal-cortical brain regions develops considerably across childhood, but less is known about the heritability of these networks at this age. We tested the heritability of limbic/subcortical-cortical and limbic/subcortical-subcortical functional brain connectivity in 7- to 9-year-old twins (N = 220), focusing on two key limbic/subcortical structures: the ventral striatum and the amygdala, given their combined influence on changing incentivised behavior during childhood and adolescence. Whole brain analyses with ventral striatum (VS) and amygdala as seeds in genetically independent groups showed replicable functional connectivity patterns. The behavioral genetic analyses revealed that in general VS and amygdala connectivity showed distinct influences of genetics and environment. VS-prefrontal cortex connections were best described by genetic and unique environmental factors (the latter including measurement error), whereas amygdala-prefrontal cortex connectivity was mainly explained by environmental influences. Similarities were also found: connectivity between both the VS and amygdala and ventral anterior cingulate cortex (vACC) showed influences of shared environment, while connectivity with the orbitofrontal cortex (OFC) showed heritability. These findings may inform future interventions that target behavioral control and emotion regulation, by taking into account genetic dispositions as well as shared and unique environmental factors such as child rearing.

Testing an Attachment-Based Parenting Intervention-VIPP-FC/A in Adoptive Families with Post-institutionalized Children: Do Maternal Sensitivity and Genetic Markers Count?

This study investigated the effectiveness of a newly integrated version of an intervention targeting adoptive mothers' positive parenting for promoting children's emotional availability, by testing the moderating role of both two maternal genetic polymorphisms (i.e., 5HTTLPR and DRD4-VNTR) and emotional availability-EA on intervention outcomes. Mothers with their children (N = 80; Mage = 42.73 years, SD = 3.79; Mage = 33.18 months, SD = 16.83 months) participated in a RCT testing the Video-Feedback Intervention to Promote Positive Parenting and Sensitive Discipline-VIPP-FC/A effectiveness. Mixed effects regression models showed a significant improvement in mother-child EA for the VIPP-intervention vs. the dummy intervention condition, with a moderating role of maternal EA on children's outcomes. No significant moderating effect was found for the two genetic polymorphisms inquired. Children's and mother's outcomes obtained are discussed.

Disorganized attachment in infancy: a review of the phenomenon and its implications for clinicians and policy-makers

Disorganized/Disoriented (D) attachment has seen widespread interest from policy makers, practitioners, and clinicians in recent years. However, some of this interest seems to have been based on some false assumptions that (1) attachment measures can be used as definitive assessments of the individual in forensic/child protection settings and that disorganized attachment (2) reliably indicates child maltreatment, (3) is a strong predictor of pathology, and (4) represents a fixed or static "trait" of the child, impervious to development or help. This paper summarizes the evidence showing that these four assumptions are false and misleading. The paper reviews what is known about disorganized infant attachment and clarifies the implications of the classification for clinical and welfare practice with children. In particular, the difference between disorganized attachment and attachment disorder is examined, and a strong case is made for the value of attachment theory for supportive work with families and for the development and evaluation of evidence-based caregiving interventions.

Cumulative prenatal exposure to adversity reveals associations with a broad range of neurodevelopmental outcomes that are moderated by a novel, biologically informed polygenetic score based on the serotonin transporter solute carrier family C6, member 4 (SLC6A4) gene expression

While many studies focus on the association between early life adversity and the later risk for psychopathology, few simultaneously explore diverse forms of environmental adversity. Moreover, those studies that examined the cumulative impact of early life adversity focus uniquely on postnatal influences. The objective of this study was to focus on the fetal period of development to construct and validate a cumulative prenatal adversity score in relation to a wide range of neurodevelopmental outcomes. We also examined the interaction of this adversity score with a biologically informed genetic score based on the serotonin transporter gene. Prenatal adversities were computed in two community birth cohorts using information on health during pregnancy, birth weight, gestational age, income, domestic violence/sexual abuse, marital strain, as well as maternal smoking, anxiety, and depression. A genetic score based on genes coexpressed with the serotonin transporter in the amygdala, hippocampus, and prefrontal cortex during prenatal life was constructed with an emphasis on functionally relevant single nucleotide polymorphisms, that is, expression quantitative trait loci. Prenatal adversities predicted a wide range of developmental and behavioral alterations in children as young as 2 years of age in both cohorts. There were interactions between the genetic score and adversities for several domains of the Child Behavior Checklist (CBCL), with pervasive developmental problems remaining significant adjustment for multiple comparisons. Scores combining different prenatal adverse exposures predict childhood behavior and interact with the genetic background to influence the risk for psychopathology.

Plastic and immobile: Unequal intergenerational mobility by genetic sensitivity score within sibling pairs

Contrary to traditional biological arguments, the differential susceptibility model suggests genotype may moderate rather than mediate parent-child economic similarity. Using family fixed effects models of Add Health sibling data, I investigate the relationship between an index of sensitive genotypes and intergenerational mobility. Full, same sex sibling comparisons hold constant parental characteristics and address the non-random distribution of genotype that reduces internal validity in nationally representative samples. Across multiple measures of young adult financial standing, those with more copies of sensitive genotypes achieve lower economic outcomes than their sibling if they are from a low income context but fare better from a high income context. This genetic sensitivity to parental income entails lower intergenerational mobility. Results support the differential susceptibility model and contradict simplistic genetic explanations for intergenerational inequality, suggesting sensitive genotypes are not inherently positive or negative but rather increase dependence on parental income and reduce mobility.

Gene and environment interaction: Is the differential susceptibility hypothesis relevant for obesity?

The differential susceptibility model states that a given genetic variant is associated with an increased risk of pathology in negative environments but greater than average resilience in enriched ones. While this theory was first implemented in psychiatric-genetic research, it may also help us to unravel the complex ways that genes and environments interact to influence feeding behavior and obesity. We reviewed evidence on gene vs. environment interactions that influence obesity development, aiming to support the applicability of the differential susceptibility model for this condition, and propose that various environmental "layers" relevant for human development should be considered when bearing the differential susceptibility model in mind. Mother-child relationship, socioeconomic status and individual's response are important modifiers of BMI and food intake when interacting with gene variants, "for better and for worse". While only a few studies to date have investigated obesity outcomes using this approach, we propose that the differential susceptibility hypothesis is in fact highly applicable to the study of genetic and environmental influences on feeding behavior and obesity risk.

Application of environmental sensitivity theories in personalized prevention for youth substance abuse: a transdisciplinary translational perspective

Preventive interventions that target high-risk youth, via one-size-fits-all approaches, have demonstrated modest effects in reducing rates of substance use. Recently, substance use researchers have recommended personalized intervention strategies. Central to these approaches is matching preventatives to characteristics of an individual that have been shown to predict outcomes. One compelling body of literature on person × environment interactions is that of environmental sensitivity theories, including differential susceptibility theory and vantage sensitivity. Recent experimental evidence has demonstrated that environmental sensitivity (ES) factors moderate substance abuse outcomes. We propose that ES factors may augment current personalization strategies such as matching based on risk factors/severity of problem behaviors (risk severity (RS)). Specifically, individuals most sensitive to environmental influence may be those most responsive to intervention in general and thus need only a brief-type or lower-intensity program to show gains, while those least sensitive may require more comprehensive or intensive programming for optimal responsiveness. We provide an example from ongoing research to illustrate how ES factors can be incorporated into prevention trials aimed at high-risk adolescents.

Exploring genetic moderators and epigenetic mediators of contextual and family effects: From Gene × Environment to epigenetics

In the current manuscript, we provide an overview of a research program at the University of Georgia's Center for Family Research designed to expand upon rapid and ongoing developments in the fields of genetics and epigenetics. By placing those developments in the context of translational research on family and community determinants of health and well-being among rural African Americans, we hope to identify novel, modifiable environments and biological processes. In the first section of the article, we review our earlier work on genotypic variation effects on the association between family context and mental and physical health outcomes as well as differential responses to family-based intervention. We then transition to discuss our more recent research on the association of family and community environments with epigenetic processes. In this second section of the article, we begin by briefly reviewing terminology and basic considerations before describing evidence that early environments may influence epigenetic motifs that potentially serve as mediators of long-term effects of early family and community environments on longer term health outcomes. We also provide evidence that genotype may sometimes influence epigenetic outcomes. Finally, we describe our recent efforts to use genome-wide characterization of epigenetic patterns to better understand the biological impact of protective parenting on long-term shifts in inflammatory processes and its potential implications for young adult health. As will be clear, research on epigenetics as a mediator of the connections between family/community processes and a range of health outcomes is still in its infancy, but the potential to develop important insights regarding mechanisms linking modifiable environments to biological processes and long-term health outcomes already is coming into view.

Interactive effects of attachment and FKBP5 genotype on school-aged children's emotion regulation and depressive symptoms

Attachment insecurity is influenced by both environmental and genetic factors, but few studies have examined the effects of gene-environment interactions. In the context of environmental stress, a functional variant in the glucocorticoid receptor co-chaperone FKBP5 gene has been repeatedly shown to increase risk for psychiatric illness, including depression. We expand on prior work by exploring cross-sectional attachment by gene effects on both attachment insecurity and downstream physiological and behavioral measures in a diverse community sample of school-aged children (N=99, 49% girls, M_age=10.29years, 66.6% non-White) and their mothers. Specifically, we examined moderating effects of FKBP5 rs3800373 genotype on the links between parenting insensitivity (overcontrol) and child attachment. Further, we assessed whether FKBP5 moderates the links between maternal and child attachment and children's emotion regulation self-report, respiratory sinus arrhythmia (RSA) in response to a standardized laboratory stressor, and depressive symptoms. Higher levels of overcontrol predicted lower child attachment security only in FKBP5 minor allele carriers. Among children with two minor alleles (CC), attachment security was negatively associated with emotion suppression, rumination, depressive symptoms, and RSA reactivity; similarly, for these children, maternal attachment anxiety was positively associated with depressive symptoms. The findings can be conceptualized in a differential susceptibility framework, where the FKBP5 minor allele confers either risk or resilience, depending on the parenting environment.

Physical and verbal aggressive behavior and COMT genotype: Sensitivity to the environment

Catechol-O-methyltransferase (COMT) genotype has been implicated as a vulnerability factor for several psychiatric diseases as well as aggressive behavior, either directly, or in interaction with an adverse environment. The present study aimed at investigating the susceptibility properties of COMT genotype to adverse and favorable environment in relation to physical and verbal aggressive behavior. The COMT Val158Met polymorphism was genotyped in a Swedish population-based cohort including 1,783 individuals, ages 20-24 years (47% males). A significant three-way interaction was found, after correction for multiple testing, between COMT genotype, exposure to violence, and parent-child relationship in association with physical but not verbal aggressive behavior. Homozygous for the Val allele reported lower levels of physical aggressive behavior when they were exposed to violence and at the same time experienced a positive parent-child relationship compared to Met carriers. Thus, susceptibility properties of COMT genotype were observed in relation to physical aggressive behavior supporting the hypothesis that COMT genotypes are modifying the sensitivity to environment that confers either risk or protection for aggressive behavior. As these are novel findings, they warrant further investigation and replication in independent samples. © 2016 Wiley Periodicals, Inc.

Parental loss of family members within two years of offspring birth predicts elevated absorption scores in college

Liotti proposed that interactions during infancy with a parent suffering unresolved loss could lead to vulnerabilities to altered states of consciousness. Hesse and van IJzendoorn provided initial support for Liotti’s hypothesis, finding elevated scores on Tellegen’s Absorption Scale - a normative form of dissociation - for undergraduates reporting that their parents had experienced the loss of family members within two years of their birth. Here, we replicated the above findings in a large undergraduate sample (N = 927). Additionally, we investigated mother’s and father’s losses separately. Perinatal losses, including miscarriage, were also considered. Participants reporting that the mother or both parents had experienced loss within two years of their birth scored significantly higher on absorption than those reporting only perinatal, only father, or no losses. While not applicable to the assessment of individuals, the brief loss questionnaire utilized here could provide a useful addition to selected large-scale studies.

Clinical effectiveness and cost-effectiveness of parenting interventions for children with severe attachment problems: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

Services have variable practices for identifying and providing interventions for 'severe attachment problems' (disorganised attachment patterns and attachment disorders). Several government reports have highlighted the need for better parenting interventions in at-risk groups. This report was commissioned to evaluate the clinical effectiveness and cost-effectiveness of parenting interventions for children with severe attachment problems (the main review). One supplementary review explored the evaluation of assessment tools and a second reviewed 10-year outcome data to better inform health economic aspects of the main review.

DATA SOURCES

A total of 29 electronic databases were searched with additional mechanisms for identifying a wide pool of references using the Cochrane methodology. Examples of databases searched include PsycINFO (1806 to January week 1, 2012), MEDLINE and MEDLINE In-Process & Other Non-Indexed Citations (1946 to December week 4, 2011) and EMBASE (1974 to week 1, 2012). Searches were carried out between 6 and 12 January 2012.

REVIEW METHODS

Papers identified were screened and data were extracted by two independent reviewers, with disagreements arbitrated by a third independent reviewer. Quality assessment tools were used, including quality assessment of diagnostic accuracy studies - version 2 and the Cochrane risk of bias tool. Meta-analysis of randomised controlled trials (RCTs) of parenting interventions was undertaken. A health economics analysis was conducted.

RESULTS

The initial search returned 10,167 citations. This yielded 29 RCTs in the main review of parenting interventions to improve attachment patterns, and one involving children with reactive attachment disorder. A meta-analysis of eight studies seeking to improve outcome in at-risk populations showed statistically significant improvement in disorganised attachment. The interventions saw less disorganised attachment at outcome than the control (odds ratio 0.47, 95% confidence interval 0.34 to 0.65; p < 0.00001). Much of this focused around interventions improving maternal sensitivity, with or without video feedback. In our first supplementary review, 35 papers evaluated an attachment assessment tool demonstrating validity or psychometric data. Only five reported test-retest data. Twenty-six studies reported inter-rater reliability, with 24 reporting a level of 0.7 or above. Cronbach's alphas were reported in 12 studies for the comparative tests (11 with α > 0.7) and four studies for the reference tests (four with α > 0.7). Three carried out concurrent validity comparing the Strange Situation Procedure (SSP) with another assessment tool. These had good sensitivity but poor specificity. The Disturbances of Attachment Interview had good sensitivity and specificity with the research diagnostic criteria (RDC) for attachment disorders. In our supplementary review of 10-year outcomes in cohorts using a baseline reference standard, two studies were found with disorganised attachment at baseline, with one finding raised psychopathology in adolescence. Budget impact analysis of costs was estimated because a decision model could not be justifiably populated. This, alongside other findings, informed research priorities.

LIMITATIONS

There are relatively few UK-based clinical trials. A 10-year follow-up, while necessary for our health economists for long-term sequelae, yielded a limited number of papers.

CONCLUSIONS

Maternal sensitivity interventions show good outcomes in at-risk populations, but require further research with complex children. The SSP and RDC for attachment disorders remain the reference standards for identification until more concurrent and predictive validity research is conducted. A birth cohort with sequential attachment measures and outcomes across different domains is recommended with further, methodologically sound randomised controlled intervention trials. The main area identified for future work was a need for good-quality RCTs in at-risk groups such as those entering foster care or adoption.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42011001395.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Borderline Personality Disorder: Why 'fast and furious'?

The term 'Borderline Personality Disorder' (BPD) refers to a psychiatric syndrome that is characterized by emotion dysregulation, impulsivity, risk-taking behavior, irritability, feelings of emptiness, self-injury and fear of abandonment, as well as unstable interpersonal relationships. BPD is not only common in psychiatric populations but also more prevalent in the general community than previously thought, and thus represents an important public health issue. In contrast to most psychiatric disorders, some symptoms associated with BPD may improve over time, even without therapy, though impaired social functioning and interpersonal disturbances in close relationships often persist. Another counterintuitive and insufficiently resolved question is why depressive symptoms and risk-taking behaviors can occur simultaneously in the same individual. Moreover, there is an ongoing debate about the nosological position of BPD, which impacts on research regarding sex differences in clinical presentation and patterns of comorbidity.In this review, it is argued that many features of BPD may be conceptualized within an evolutionary framework, namely behavioral ecology. According to Life History Theory, BPD reflects a pathological extreme or distortion of a behavioral 'strategy' which unconsciously aims at immediate exploitation of resources, both interpersonal and material, based on predictions shaped by early developmental experiences. Such a view is consistent with standard medical conceptualizations of BPD, but goes beyond classic 'deficit'-oriented models, which may have profound implications for therapeutic approaches.

Shedding light on the specificity of school-aged children's attachment narratives

A prominent research tradition within the field of attachment involves analyzing relationship narratives for qualities thought to reveal important information regarding the organization of attachment, and the different ways in which attachment insecurity presents. Researchers increasingly use this method to assess attachment in middle childhood, but further work needs to be conducted with respect to the divergent validity of attachment narratives in this age range. Thus, the current study examined differential associations between children's discursive style and linguistic behavior when completing an attachment interview (Child Attachment Interview [CAI]) and Non-Relational Interview (NRI). In addition, the discriminant validity of attachment narratives was assessed in predicting children's physiological reactivity to a relational challenge. Children (N = 125) completed the NRI and the CAI at Time 1. A subset of the original sample (n = 64) completed another assessment 1.5 years later involving simulated non-relational and relational challenges. While narrative coherence was moderately associated across the two interviews, CAI narrative coherence uniquely predicted reactivity to a relational probe. We discuss implications for understanding children's narrative styles across discourse topics as well as the significance of the results for using attachment interviews in this age range.

Differential Vulnerability to Early-Life Parental Death: The Moderating Effects of Family Suicide History on Risks for Major Depression and Substance Abuse in Later Life

Only a portion of those individuals exposed to parental death in early life (PDE) develop behavioral health disorders. We utilized demographic pedigree data from the Utah Population Database to test for differential vulnerability to PDE by creating a risk score of familial susceptibility to suicide (FS) at the population level. Using logistic panel regression models, we tested for multiplicative interactions between PDE and FS on the risks of major depressive disorder (MDD) and substance abuse (SA), measured using Medicare claims, after age 65. The final sample included 155,983 individuals (born 1886-1944), yielding 1,431,060 person-years at risk (1992-2009). Net of several potential confounders, including probability of survival to age 65, we found an FS × PDE interaction for females, in which PDE and FS as main effects had no impact but jointly increased MDD risk. No statistically significant main or interactive effects were found for SA among females or for either phenotype among males. Our findings are consistent with a differential vulnerability model for MDD in females, in which early-life stress increases the risk for poor behavioral health only among the vulnerable. Furthermore, we demonstrate how demographic and pedigree data might serve as tools for investigating differential vulnerability hypotheses.

Differential Susceptibility of the Developing Brain to Contextual Adversity and Stress

A swiftly growing volume of literature, comprising both human and animal studies and employing both observational and experimental designs, has documented striking individual differences in neurobiological sensitivities to environmental circumstances within subgroups of study samples. This differential susceptibility to social and physical environments operates bidirectionally, in both adverse and beneficial contexts, and results in a minority subpopulation with remarkably poor or unusually positive trajectories of health and development, contingent upon the character of environmental conditions. Differences in contextual susceptibility appear to emerge in early development, as the interactive and adaptive product of genetic and environmental attributes. This paper surveys what is currently known of the mechanisms or mediators of differential susceptibility, at the levels of temperament and behavior, physiological systems, brain circuitry and neuronal function, and genetic and epigenetic variation. It concludes with the assertion that differential susceptibility is inherently grounded within processes of biological moderation, the complexities of which are at present only partially understood.

Genetic mechanisms of parenting

This article is part of a Special Issue "Parental Care". The complexities of parenting behavior in humans have been studied for decades. Only recently did we begin to probe the genetic and epigenetic mechanisms underlying these complexities. Much of the research in this field continues to be informed by animal studies, where genetic manipulations and invasive tools allow to peek into and directly observe the brain during the expression of maternal behavior. In humans, studies of adult twins who are parents can suggest dimensions of parenting that might be more amenable to a genetic influence. Candidate gene studies can test specific genes in association with parental behavior based on prior knowledge of those genes' function. Gene-by-environment interactions of a specific kind indicating differential susceptibility to the environment might explain why some parents are more resilient and others are more vulnerable to stressful life events. Epigenetic studies can provide the bridge often necessary to explain why some individuals behave differently from others despite common genetic influences. There is a much-needed expansion in parenting research to include not only mothers as the focus-as has been the case almost exclusively to date-but also fathers, grandparents, and other caregivers.

Interacting effects of maternal responsiveness, infant regulatory problems and dopamine D4 receptor gene in the development of dysregulation during childhood: A longitudinal analysis

Recent longitudinal studies have indicated that affective and behavioral dysregulation in childhood is associated with an increased risk for various negative outcomes in later life. However, few studies to date have examined early mechanisms preceding dysregulation during early childhood. Aim of this study was to elucidate early mechanisms relating to dysregulation in later life using data from an epidemiological cohort study on the long-term outcome of early risk factors from birth to adulthood. At age 3 months, mothers and infants were videotaped during a nursing and playing situation. Maternal responsiveness was evaluated by trained raters. Infant regulatory problems were assessed on the basis of a parent interview and direct observation by trained raters. At age 8 and 11 years, 290 children (139 males) were rated on the Child Behavior Checklist (CBCL). Additionally, participants were genotyped for the dopamine D4 receptor (DRD4) exon 3 VNTR polymorphism. A significant three-way interaction between maternal responsiveness, DRD4 genotype and infant regulatory problems was detected predicting the CBCL-dysregulation profile (CBCL-DP). Carriers of the DRD4 7r allele with regulatory problems at age 3 months showed significantly more behavior problems associated with the CBCL-DP during childhood when exposed to less maternal responsiveness. In contrast, no effect of maternal responsiveness was observed in DRD4 7r carriers without infant regulatory problems and in non-carriers of the DRD4 7r allele. This prospective longitudinal study extends earlier findings regarding the association of the CBCL-DP with early parenting and later psychopathology, introducing both DRD4 genotype and infant regulatory problems as important moderators.