Measured Gene-Environment Interactions in Psychopathology: Concepts, Research Strategies, and Implications for Research, Intervention, and Public Understanding of Genetics

A multifaceted approach to identifying and managing juvenile delinquency by integrating psycho-physiological indicators

To understand and treat juvenile delinquency, the study explores the relevance of psycho-physiological indicators. It also emphasizes the necessity for thorough research to minimize the gap existing between psycho-physiological measurements and conventional psychosocial components. The study focuses on the relevance of personality features, habituation, and autonomic arousal required to monitor the proper management of delinquent conduct. Through the integration of biological, psychological, and social elements into a multidimensional approach, researchers can uncover novel insights and create cutting-edge therapies for youths who are at risk of delinquent behavior. The study proposes to develop a comprehensive framework that considers biological antecedents in addition to conventional metrics to reach the root cause of delinquency; thereby drawing special attention to current literature and research that emphasizes the psycho-physiological correlates of delinquency. By examining the complex interactions between stress, physiology, emotions, behavior, and social structures, the study highlights the intricacy of delinquent conduct and the necessity for adopting a multifaceted strategy to fully address the problematic areas. Future research paths are emphasized, with a focus on the significance of longitudinal studies, moderating and mediating variables, and creative treatment techniques. By utilizing psycho-physiological markers and psychosocial traits, researchers can tailor intervention strategies to meet individual needs effectively. Early identification of psycho-physiological deficits in children is crucial for implementing successful behavior modification techniques and promoting the well-being of future generations. This is expected to help the government agencies to save time and public money.

Polygene by environment interactions predicting depressive outcomes

Depression is a major public health problem with a continued need to uncover its etiology. Current models of depression contend that gene-by-environment (G × E) interactions influence depression risk, and further, that depression is polygenic. Thus, recent models have emphasized two polygenic approaches: a hypothesis-driven multilocus genetic profile score (MGPS; "MGPS × E") and a polygenic risk score (PRS; "PRS × E") derived from genome-wide association studies (GWAS). This review for the first time synthesizes current knowledge on polygene by environment "P × E" interaction research predicting primarily depression-related outcomes, and in brief, neurobiological outcomes. The "environment" of focus in this project is stressful life events. It further discusses findings in the context of differential susceptibility and diathesis-stress theories-two major theories guiding G × E work. This synthesis indicates that, within the MGPS literature, polygenic scores based on the serotonin system, the HPA axis, or across multiple systems, interact with environmental stress exposure to predict outcomes at multiple levels of analyses and most consistently align with differential susceptibility theory. Depressive outcomes are the most studied, but neuroendocrine, and neuroimaging findings are observed as well. By contrast, vast methodological differences between GWAS-based PRS studies contribute to mixed findings that yield inconclusive results.

From the early scars to the vicissitudes of old age: A bibliometric analysis revealing childhood adversity and aging

BACKGROUND

Adversity suffered in childhood may profoundly affect aging over the subsequent life cycle. The field of childhood adversity and aging has amassed a certain number of publications, but there are no bibliometric studies in this field.

METHODS

Publications in 10 years on childhood adversity and aging were searched in the Web of Science Core Collection. Bibliometric tools were used to analyze and visualize these publications by country, institution, journal, author, keyword, research area, and co-citation.

RESULTS

Four hundred thirty-five publications were retrieved from 2014 to September 21, 2023, with a 4.9% annual growth rate. The United States (251), University of California, San Francisco (59), Elissa S. Epel (11), and Psychoneuroendocrinology (29) were the countries, institutions, authors, and journals contributing the highest number of publications in this field, respectively. "Early-life stress" (87), "depression" (82), "childhood trauma" (69), and "aging" (60) were the keywords that appeared more frequently.

CONCLUSIONS

This is the first bibliometric study on childhood adversity and aging. The United States dominates the field regarding publication numbers, research institutions, and researchers. Publications in this field are interdisciplinary, covering several critical subject areas and having far-reaching impacts, with gerontology, neurosciences, psychology, and psychiatry at the core.

Theory of Mind: A Brief Review of Candidate Genes

Deficits in theory of mind (ToM), known as the ability to understand the other's mind, have been associated with several psychopathological outcomes. The present systematic review aims to summarize the results of genetic studies that investigated gene polymorphisms associated with mentalization performance tasks in children and adults. The systematic review was carried out following PRISMA guidelines, and the literature search was conducted in PubMed and EBSCOhost using the following keywords: 'theory of mind, mentalizing, mindreading' and 'gene, genetic basis'. Nineteen studies met the eligibility criteria for inclusion. Most of the literature focused on the role of DRD4, DAT1, OXTR, OXT, COMT, ZNF804A, AVP, AVPR, SCL6A4, EFHC2, MAO-A, and the family of GTF2I genes in influencing ToM. However, controversial results emerged in sustaining the link between specific genetic polymorphisms and mentalization abilities in children and adults. Available data show heterogeneous outcomes, with studies reporting an association between the same family genes in subjects of the same age and other studies reporting no correlation. This does not allow us to draw any solid conclusions but paves the way for exploring genes involved in ToM tasks.

Parental Nurturance Moderates the Etiology of Youth Resilience

Parenting behaviors are among the most robust predictors of youth resilience to adversity. Critically, however, very few studies examining these effects have been genetically-informed, and none have considered parenting as an etiologic moderator of resilience. What's more, despite the multidimensionality of resilience, extant etiologic literature has largely focused on a single domain. The current study sought to fill these respective gaps in the literature by examining whether and how parental nurturance shapes the etiology of academic, social, and psychological resilience, respectively. We employed a unique sample of twins (N = 426 pairs; ages 6-11) exposed to moderate-to-severe levels of environmental adversity (i.e., family poverty, neighborhood poverty, community violence) from the Twin Study of Behavioral and Emotional Development in Children. As expected, parental nurturance was positively correlated with all forms of resilience. Extended univariate genotype-by-environment interaction models revealed that parental nurturance significantly moderated genetic influences on all three domains of resilience (academic resilience A1= -0.53, psychological resilience A1= -1.22, social resilience A1= -0.63; all p < .05), such that as parental nurturance increased, genetic influences on youth resilience decreased. Put another way, children experiencing high levels of parental nurturance were more resilient to disadvantage, regardless of their genetic predisposition towards resilience. In the absence of nurturing parenting, however, genetic influences played an outsized role in the origins of resilience. Such findings indicate that parental nurturance may serve as a malleable protective factor that increases youth resilience regardless of genetic influences.

Relationship between gene-environment interaction and obsessive-compulsive disorder: A systematic review

BACKGROUND

Gene-environment interaction (G × E) refers to the change of genetic effects under the participation of environmental factors resulting in differences in genetic expression. G × E has been studied in the occurrence and development of many neuropsychiatric disorders, including obsessive-compulsive disorder (OCD).

AIM

A systematic review was conducted to investigate the role of G × E plays in OCD. This review explored the relationship between G × E and the susceptibility to OCD occurrence, disease progression, and treatment response.

METHODS

This systematic literature search was performed using Web of Science, PubMed, Cochrane Library, and CNKI. Seven studies were selected, which included seven genes (BDNF, COMT, MAO, 5-HTT, SMAD4, PGRN, and SLC1A1) polymorphisms, polygenic risk score (PRS), and two environmental factors (childhood trauma and stressful life events).

RESULTS

Information from this systematic review indicated that G × E increased the susceptibility to OCD, played a crucial role in the clinical characteristics, and had an inconsistent impact on treatment response of OCD.

FUTURE DIRECTIONS

The multi-omics studies and the inclusion of G × E in future GWAS studies of OCD should be drawn more attention, which may contribute to a deeper understanding of the etiology of OCD as well as guide therapeutic interventions for the disease.

Beyond orchids and dandelions: Susceptibility to environmental influences is not bimodal

This study focused on generality versus specificity of susceptibility of effects of eight family and child-care exposures measured between 3 and 54 months of age (e.g., sensitive parenting, child-care quality) on five child development outcomes assessed at age 4.5 years (e.g. behavior problems, preacademic skill), using data from The National Institute of Child Health and Human Development (NICHD) Study of Early Child Care and Youth Development (n = 1,364, boys = 705; White = 1,097, Black = 176, other = 91), while applying a novel influence-statistics method. Results indicated that susceptibility across the environment-predictor:child-outcome associations is normally rather than bimodally (i.e., orchid-dandelion) distributed. Analysis of susceptibility documents both domain generality and specificity of developmental plasticity, with effect sizes proving small in the former case. As predicted, children who as infants had difficult temperaments or who scored higher on a polygenic-plasticity score (serotonin-transporter-linked promoter region [5-HTTLPR], dopamine receptor D4 [DRD4], brain-derived neurotrophic factor [BDNF]) proved somewhat more susceptible to some of the environmental effects investigated. Results lead to the recommendation that two-types-of-individuals vis-a-vis susceptibility to environmental influences be questioned and general-trait conceptions of susceptibility be further investigated.

Conduct Problems and Hair Cortisol Concentrations Decrease in School-Aged Children after VIPP-SD: A Randomized Controlled Trial in Two Twin Cohorts

The Video-feedback Intervention to promote Positive Parenting and Sensitive Discipline (VIPP-SD) is effective in increasing parental sensitivity and sensitive discipline, and aims to decrease child behavior problems. Changes in quality of parenting may be accompanied by effects on child stress levels. However, studies of VIPP-SD effects on child behavior problems have shown mixed results and there are no studies to date of the effect of the intervention on children's stress levels, as measured by hair cortisol concentration (HCC). Furthermore, differences in intervention effectiveness may be explained by differential susceptibility factors. We hypothesized that the effects of the VIPP-SD on child behavior problems might be moderated by currently available child polygenic scores of differential susceptibility (PGS-DS). In the current pre-registered trial, we randomly assigned 40% of n = 445 families with school-aged twin children to the intervention group. The VIPP-SD was successful in decreasing both children's conduct problems and HCC. Effects were not moderated by available child PGS-DS. We conclude that a brief, home-based video-feedback parenting intervention can decrease child behavior problems and affect the child's stress-related neuroendocrine system as assessed with hair cortisol. In future studies, more specific PGS-DS for externalizing behaviors should be used as well as parental PGS-DS.

Longitudinal Influences of DRD4 Polymorphism and Early Maternal Caregiving on Personality Development and Problem Behavior in Middle Childhood and Adolescence

Most studies examining gene-environment effects on self-regulation focus on outcomes early childhood or adulthood. However, only a few studies investigate longitudinal effects during middle childhood and adolescence and compare two domains of early caregiving. In a longitudinal follow-up with a sample of N = 87, we studied the effects of differences in the DRD4 tandem repeat polymorphisms and two domains of early maternal caregiving quality on children's personality development using Block's California Child Q-Set (CCQ) at age six and age 12 and on problem behavior at ages six and seven. Early maternal regulation quality predicted later ego-resiliency and aggressiveness. In addition, significant gene-environment interactions revealed that children with the 7+ DRD4 tandem repeat polymorphism and poor maternal regulation quality in infancy showed lower scores in ego-resiliency and higher scores in ego-undercontrol and CCQ aggressiveness. In contrast, children who had experienced effective maternal regulation in infancy showed a comparable level in personality traits and problem behavior as the DRD4 7- group independent of the levels of maternal regulatory behavior. Similarly, longitudinal caregiving × DRD4 interactions were found for behavior problems in middle childhood, especially for oppositional-aggression, inattentive-hyperactivity, and social competence. Early caregiving effects were only found for maternal regulation quality, but not for maternal responsiveness. Effective early maternal regulation in infancy can moderate the negative effect of DRD4 7+ on children's self-regulation in middle childhood and adolescence. However, maternal responsiveness has no comparable effects. It seems relevant to consider several dimensions of early caregiving and to also measure the environment in more detail in gene-environment studies.

Cross-Cultural Communication on Social Media: Review From the Perspective of Cultural Psychology and Neuroscience

Introduction

In recent years, with the popularity of many social media platforms worldwide, the role of “virtual social network platforms” in the field of cross-cultural communication has become increasingly important. Scholars in psychology and neuroscience, and cross-disciplines, are attracted to research on the motivation, mechanisms, and effects of communication on social media across cultures.

Methods and Analysis

This paper collects the co-citation of keywords in “cultural psychology,” “cross-culture communication,” “neuroscience,” and “social media” from the database of web of science and analyzes the hotspots of the literature in word cloud.

Results

Based on our inclusion criteria, 85 relevant studies were extracted from a database of 842 papers. There were 44 articles on cultural communication on social media, of which 26 were from the perspective of psychology and five from the perspective of neuroscience. There are 27 articles that focus on the integration of psychology and neuroscience, but only a few are related to cross-cultural communication on social media.

Conclusion

Scholars have mainly studied the reasons and implications of cultural communication on social media from the perspectives of cultural psychology and neuroscience separately. Keywords “culture” and “social media” generate more links in the hot map, and a large number of keywords of cultural psychology and neuroscience also gather in the hot map, which reflects the trend of integration in academic research. While cultural characteristics have changed with the development of new media and virtual communities, more research is needed to integrate the disciplines of culture, psychology, and neuroscience.

Outcomes of serious antisocial behavior from childhood to early adulthood in two Puerto Rican samples in two contexts

PURPOSE

The patterns or trajectories of serious antisocial behavior (ASB) in children are examined to determine the extent to which context, gender, and the severity and persistence of ASB from childhood/early adolescence to later adolescence/early adulthood is associated with negative outcomes.

METHODS

A four wave longitudinal study obtained data on two multi-stage probability household samples of Puerto Rican background children (5-13 years at baseline) living in the San Juan Metropolitan Area of Puerto Rico (PR) and the South Bronx (SBx) of New York. The outcomes studied were any psychiatric disorder including substance use disorders and teenage pregnancy.

RESULTS

Both males and females raised in the SBx had much higher risk of serious ASB (42.3%) as compared to those in PR (17.8%). Concurrent ASB4 + in the fourth wave was strongly related to SUD and MDD for both males and females at Wave 4.

CONCLUSIONS

Serious ASB is likely to persist at least to the next developmental period of a child and is likely to be associated with substance use disorders and major depression later in life.

Interactions Between Experience, Genotype and Sex in the Development of Individual Coping Strategies

Coping strategies, the first line of defense against adversities, develop through experience. There is consistent evidence that both genotype and sex contribute to the development of dysfunctional coping, leading to maladaptive outcomes of adverse experiences or to adaptive coping that fosters rapid recovery even from severe stress. However, how these factors interact to influence the development of individual coping strategies is just starting to be investigated. In the following review, we will consider evidence that experience, sex, and genotype influence the brain circuits and neurobiological processes involved in coping with adversities and discuss recent results pointing to the specific effects of the interaction between early experiences, genotype, and stress in the development of functional and dysfunctional coping styles.

From Genome-Wide to Environment-Wide: Capturing the Environome

Genome-wide association (GWA) studies have shown that genetic influences on individual differences in affect, behavior, and cognition are driven by thousands of DNA variants, each with very small effect sizes. Here, we propose taking inspiration from GWA studies for understanding and modeling the influence of the environment on complex phenotypes. We argue that the availability of DNA microarrays in genetic research is comparable with the advent of digital technologies in psychological science that enable collecting rich, naturalistic observations in real time of the environome, akin to the genome. These data can capture many thousand environmental elements, which we speculate each influence individual differences in affect, behavior, and cognition with very small effect sizes, akin to findings from GWA studies about DNA variants. We outline how the principles and mechanisms of genetic influences on psychological traits can be applied to improve the understanding and models of the environome.

Unraveling the complex interplay between genes, environment, and climate in ALS

Various genetic and environmental risk factors have been implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS). Despite this, the cause of most ALS cases remains obscure. In this review, we describe the current evidence implicating genetic and environmental factors in motor neuron degeneration. While the risk exerted by many environmental factors may appear small, their effect could be magnified by the presence of a genetic predisposition. We postulate that gene-environment interactions account for at least a portion of the unknown etiology in ALS. Climate underlies multiple environmental factors, some of which have been implied in ALS etiology, and the impact of global temperature increase on the gene-environment interactions should be carefully monitored. We describe the main concepts underlying such interactions. Although a lack of large cohorts with detailed genetic and environmental information hampers the search for gene-environment interactions, newer algorithms and machine learning approaches offer an opportunity to break this stalemate. Understanding how genetic and environmental factors interact to cause ALS may ultimately pave the way towards precision medicine becoming an integral part of ALS care.

Repetitive and Inflexible Active Coping and Addiction-like Neuroplasticity in Stressed Mice of a Helplessness-Resistant Inbred Strain

Dysfunctional coping styles are involved in the development, persistence, and relapse of psychiatric diseases. Passive coping with stress challenges (helplessness) is most commonly used in animal models of dysfunctional coping, although active coping strategies are associated with generalized anxiety disorder, social anxiety disorder, panic, and phobias as well as obsessive-compulsive and post-traumatic stress disorder. This paper analyzes the development of dysfunctional active coping strategies of mice of the helplessness–resistant DBA/2J (D2) inbred strain, submitted to temporary reduction in food availability in an uncontrollable and unavoidable condition. The results indicate that food-restricted D2 mice developed a stereotyped form of food anticipatory activity and dysfunctional reactive coping in novel aversive contexts and acquired inflexible and perseverant escape strategies in novel stressful situations. The evaluation of FosB/DeltaFosB immunostaining in different brain areas of food-restricted D2 mice revealed a pattern of expression typically associated with behavioral sensitization to addictive drugs and compulsivity. These results support the conclusion that an active coping style represents an endophenotype of mental disturbances characterized by perseverant and inflexible behavior.

Alcohol use disorders among adult children of alcoholics (ACOAs): Gene-environment resilience factors

Both genetic and early environmental factors contribute to the pathogenesis of Alcohol Use Disorder (AUD). Gender and psychopathology symptoms might further moderate this association, resulting in an impairment of both the dopaminergic and serotoninergic pathways that sustain the binge, withdrawal and craving cycle. In a sample of of adult children of alcoholic parents (ACOAs) (n = 107) we compared those with and without an AUD, on socio-demographic variables, adverse childhood experiences, psychopathology symptoms and two polymorphisms associated with an impaired serotoninergic and dopaminergic neurotransmission (5HTTLPR and Taq1A/DRD2). A logistic regression revealed that an early caring environment might lower the risk of developing an AUD. When controlling for the actual psychopathology symptoms, being male and having the genotype associated with an impaired dopaminergic neurotransmission were still associated with AUD. Results were confirmed by an unsupervised approach that showed how the clusters characterised by being male and having the high risk genotypes were still associated with AUD compared to being female without the unfavourable dopamine genotype.Our results point to the need for implementing prevention strategies aimed at creating a caring environment especially in those families with an alcoholic parent. We further suggest that psycho-education as a symptom recognition and avoiding self-medication could improve the outcome in those subjects at higher risk, especially males.

Differential susceptibility 2.0: Are the same children affected by different experiences and exposures?

Differential susceptibility theory stipulates that some children are more susceptible than others to both supportive and adverse developmental experiences/exposures. What remains unclear is whether the same individuals are most affected by different exposures (i.e., domain general vs. specific). We address this issue empirically for the first time using, for illustrative and proof-of-principle purposes, a novel influence-statistics' method with data from the National Institute of Child Health and Human Development (NICHD) Study of Early Child Care. Results indicated that previously documented effects of greater quality of care on enhanced pre-academic skills and greater quantity of care on more behavior problems apply mostly to different children. Analyses validating the new method indicated, as predicted, that (a) the quantity-of-care effect applied principally to children from more socioeconomically advantaged families and that (b) being highly susceptible to both, one or neither childcare effect varied as a function of a three-gene, polygenic-plasticity score (serotonin transporter linked polymorphic region [5-HTTLPR], dopamine receptor D4 [DRD4], brain-derived neurotrophic factor [BDNF]) in a dose-response manner (i.e., 2>1>0). While domain-specific findings involving child-care effects cannot be generalized to other environmental influences, the influence-statistics' approach appears well suited for investigating the generality-specificity of environment effects, that is, of "differential, differential susceptibility."

The evolutionary genetics of personality

Genetic influences on personality differences are ubiquitous, but their nature is not well understood. A theoretical framework might help, and can be provided by evolutionary genetics. We assess three evolutionary genetic mechanisms that could explain genetic variance in personality differences: selective neutrality, mutation‐selection balance, and balancing selection. Based on evolutionary genetic theory and empirical results from behaviour genetics and personality psychology, we conclude that selective neutrality is largely irrelevant, that mutation‐selection balance seems best at explaining genetic variance in intelligence, and that balancing selection by environmental heterogeneity seems best at explaining genetic variance in personality traits. We propose a general model of heritable personality differences that conceptualises intelligence as fitness components and personality traits as individual reaction norms of genotypes across environments, with different fitness consequences in different environmental niches. We also discuss the place of mental health in the model. This evolutionary genetic framework highlights the role of gene‐environment interactions in the study of personality, yields new insight into the person‐situation‐debate and the structure of personality, and has practical implications for both quantitative and molecular genetic studies of personality. Copyright © 2007 John Wiley & Sons, Ltd.

The Cascade Effect of Parent Dysfunction: An Emotion Socialization Transmission Framework

The current study tested a preliminary cascade model of parent dysfunction—i.e., internalizing psychopathology and emotion dysregulation—whereby parent dysfunction is transmitted to children through the impact of parental emotion socialization on child emotion regulation. Participants were 705 mothers (M_age = 36.17, SD = 7.55) and fathers (M_age = 35.43, SD = 6.49) of children aged 8 to 12 years who self-reported on their internalizing psychopathology, emotion regulation difficulties, and emotion socialization practices, and on their child’s internalizing psychopathology and emotion regulation. Using a split sample method, we employed a data-driven approach to develop a conceptual model from our initially proposed theoretical model with the first subsample (n = 352, 51% mothers), and then validated this model in a second subsample (n = 353, 49% mothers). Results supported a model in which the transmission of dysfunction from parent to child was sequentially mediated by unsupportive parental emotion socialization—but not supportive parental emotion socialization—and child emotion dysregulation. The indirect effects from the final model did not differ by parent gender. Findings provide preliminary support for a mechanism by which maternal and paternal internalizing psychopathology and emotion dysregulation disrupt parental emotion socialization by increasing unsupportive emotion socialization practices, which impacts children’s development of emotion regulation skills and risk for internalizing psychopathology.

Three phases of Gene × Environment interaction research: Theoretical assumptions underlying gene selection

Some Gene × Environment interaction (G×E) research has focused upon single candidate genes, whereas other related work has targeted multiple genes (e.g., polygenic scores). Each approach has informed efforts to identify individuals who are either especially vulnerable to the negative effects of contextual adversity (diathesis stress) or especially susceptible to both positive and negative contextual conditions (differential susceptibility). A critical step in all such molecular G×E research is the selection of genetic variants thought to moderate environmental influences, a subject that has not received a great deal of attention in critiques of G×E research (beyond the observation of small effects of individual genes). Here we conceptually distinguish three phases of G×E work based on the selection of genes presumed to moderate environmental effects and the theoretical basis of such decisions: (a) single candidate genes, (b) composited (multiple) candidate genes, and (c) GWAS-derived polygenic scores. This illustrative, not exhaustive, review makes it clear that implicit or explicit theoretical assumptions inform gene selection in ways that have not been clearly articulated or fully appreciated.

Risk for Substance Use Disorders in young adulthood: Associations with developmental experiences of homelessness, foster care, and adverse childhood experiences

BACKGROUND

Multiple developmental risk factors for Substance Use Disorders (SUDs) during young adulthood have been identified. In this investigation, we examined the impact of homelessness, foster care, and adverse childhood experiences (ACEs) prior to 12th grade on the development of three common SUDs during young adulthood-Alcohol Use Disorder (AUD), Tobacco Use Disorder (TUD) and Cannabis Use Disorder (CUD). Our hypothesis was that while both homelessness and ACEs are significant risk factors for young adult SUDs, foster care involvement might convey protection.

METHODS

Using nationally representative data from the National Longitudinal Study of Adolescent to Adult Health, measures of ACEs were derived from the CDC-Kaiser ACE study, and DSM-V SUD diagnoses were derived from items originally based on DSM-IV. SUD diagnoses were binned into "mild", "moderate", and "severe" groupings. Survey-based logistic models were used to estimate risks of SUDs while controlling for demographics.

RESULTS

The results suggest that the experience of homelessness prior to 12th grade in addition to ACEs were significantly associated with the development in young adulthood of the most severe forms of AUD and TUD and all severity levels of CUD. Foster care was not associated with either risk or protection from SUDs.

CONCLUSIONS

The experience of homelessness during development may be viewed as another detrimental ACE that is a risk factor for the most common SUDs in young adulthood. Given the magnitude of the current epidemic of homelessness in the U.S., these results should raise substantial concern.

Do neighborhood social processes moderate the etiology of youth conduct problems?

BACKGROUND

Prior work has robustly suggested that social processes in the neighborhood (i.e. informal social control, social cohesion, norms) influence child conduct problems (CP) and related outcomes, but has yet to consider how these community-level influences interact with individual-level genetic risk for CP. The current study sought to do just this, evaluating neighborhood-level social processes as etiologic moderators of child CP for the first time.

METHODS

We made use of two nested samples of child and adolescent twins within the Michigan State University Twin Registry (MSUTR): 5649 families who participated in in the Michigan Twins Project (MTP) and 1013 families who participated in the Twin Study of Behavioral and Emotional Development (TBED-C). The neighborhood social processes of informal social control, social cohesion, and norms were assessed using neighborhood sampling techniques, in which residents of each twin family's neighborhood reported on the social processes in their neighborhood. Standard biometric GxE analyses evaluated the extent to which they moderated the etiology of CP.

RESULTS

The 'no moderation' model provided the best fit to the data in nearly all cases, arguing against neighborhood social processes as etiologic moderators of youth CP.

CONCLUSIONS

The neighborhood social processes evaluated here do not appear to exert their effects on child CP via etiologic moderation. The documented links between neighborhood social processes and child CP are thus likely to reflect a different etiologic process. Possibilities include environmental main effects of neighborhood social processes on child CP, or genotype-environment correlations.

Annual Research Review: Ecological momentary assessment studies in child psychology and psychiatry

BACKGROUND

Enhancements in mobile phone technology allow the study of children and adolescents' everyday lives like never before. Ecological momentary assessment (EMA) uses these advancements to allow in-depth measurements of links between context, behavior, and physiology in youths' everyday lives.

FINDINGS

A large and diverse literature now exists on using EMA to study mental and behavioral health among youth. Modern EMA methods are built on a rich tradition of idiographic inquiry focused on the intensive study of individuals. Studies of child and adolescent mental and behavioral health have used EMA to characterize lived experience, document naturalistic within-person processes and individual differences in these processes, measure familiar constructs in novel ways, and examine temporal order and dynamics in youths' everyday lives.

CONCLUSIONS

Ecological momentary assessment is feasible and reliable for studying the daily lives of youth. EMA can inform the development and augmentation of traditional and momentary intervention. Continued research and technological development in mobile intervention design and implementation, EMA-sensor integration, and complex real-time data analysis are needed to realize the potential of just-in-time adaptive intervention, which may allow researchers to reach high-risk youth with intervention content when and where it is needed most.

Parenting Practices and Adolescent Effortful Control: MAOA T941G Gene Polymorphism as a Moderator

Effortful control (EC) plays a crucial role in psychopathology disorders. Emerging studies have paid attention to the effects of G × E interaction on EC. The present study investigated interactions between monoamine oxidase A (MAOA) T941G polymorphism with parenting practices on EC in a sample of 1,531 Chinese adolescents. The adolescents completed the Early Adolescent Temperament Questionnaire-Revised (EATQ-R) EC scale and the Parenting Style Index provided during the study to assess EC and parenting practices, respectively. MAOA T941G polymorphism exerted no effect on adolescent EC; however, results revealed that the MAOA gene interacted with parental acceptance/involvement in their associations with EC among boys. Specifically, although increased levels of parental acceptance/involvement benefited all adolescents, boys with G alleles of the MAOA gene exhibited higher sensitivity to parental acceptance/involvement, compared with T carriers; this interaction was not significant among girls. This study is the first to identify MAOA × parenting interaction on adolescent EC, further contributing to the literature in MAOA gene-EC.

Interactive Effect of IGF2BP2 rs4402960 Variant, Smoking and Type 2 Diabetes

PURPOSE

Genetic and environmental factors are related to type 2 diabetes (T2D). Genetic modifiers of T2D have not been widely determined among smoking individuals. In this population-based study, we investigated the interactive association between rs4402960 polymorphism of the insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) gene and smoking with T2D among Taiwanese adults.

MATERIALS AND METHODS

We obtained genetic data collected between 2008 and 2018 for 22,039 participants (aged 30-70 years) from the Taiwan Biobank (TWB) database. These data were analyzed using the t-test, Chi-square (χ ²) test, and multiple logistic regression.

RESULTS

The mean ages for participants with and without diabetes were 58.11±8.75 and 48.58±11, respectively. Compared with the rs4402960 GG genotype, the odds ratio (OR) for T2D was 1.261 among GT and 1.545 among TT genotype individuals (p<0.05). Current smokers compared to nonsmokers were associated with a higher risk of T2D (OR=1.266, p=0.0404). There was a significant interaction between the IGF2BP2 rs4402960 variant and smoking on T2D (p = 0.0497). After stratification by rs4402960 genotypes and smoking status, the OR was substantial only in current smokers with GG genotype (OR, 1.663, p = 0.0008).

CONCLUSION

This population-based study indicated that the risk for T2D was stronger among current smoking rs4402960 GG individuals recruited between 2008 and 2019 in Taiwan.

Child Antisocial Behavior Is more Environmental in Origin in Disadvantaged Neighborhoods: Evidence Across Residents' Perceptions and Geographic Scales in Two Samples

Prior research has suggested that disadvantaged neighborhood contexts alter the etiology of youth antisocial behavior (ASB). Unfortunately, these studies have relied exclusively on governmental data collected in administratively-defined neighborhoods (e.g., Census tracts or block groups, zip codes), a less than optimal approach for studying neighborhood effects. It would thus be important to extend prior findings of GxE using neighborhood sampling techniques, in which disadvantage is assessed via resident informant-reports of the neighborhood. The current study sought to do just this, examining two independent twin samples from the Michigan State University Twin Registry. Neighborhood disadvantage was assessed via maternal and neighbor informant-reports, the latter of which were analyzed multiple ways (i.e., all neighbors within 1 km, nearest neighbor, and all neighbors within the County). Analyses revealed clear and consistent evidence of moderation by neighborhood disadvantage, regardless of informant or the specific operationalization of neighborhood. Shared environmental influences on ASB were observed to be several-fold larger in disadvantaged contexts, while genetic influences were proportionally more influential in advantaged neighborhoods. Such findings indicate that neighborhood disadvantage exerts rather profound effects on the origins of youth ASB. Efforts should now be made to identify the active ingredients of neighborhood disadvantage.

Utilising Genetically-Informed Research Designs to Better Understand Family Processes and Child Development: Implications for Adoption and Foster Care Focused Interventions

Understanding the interplay between genetic factors and family environmental processes (e.g., inter-parental relationship quality, positive versus negative parenting practices) and children's mental health (e.g., anxiety, depression, conduct problems, ADHD) in the contexts of adoption and foster-care research and practice is critical for effective prevention and intervention programme development. Whilst evidence highlights the importance of family environmental processes for the mental health and well-being of children in adoption and foster care, there is relatively limited evidence of effective interventions specifically for these families. Additionally, family-based interventions not specific to the context of adoption and foster-care typically show small to medium effects, and even where interventions are efficacious, not all children benefit. One explanation for why interventions may not work well for some is that responses to intervention may be influenced by an individual's genetic make-up. This paper summarises how genetically-informed research designs can help disentangle genetic from environmental processes underlying psychopathology outcomes for children, and how this evidence can provide improved insights into the development of more effective preventative intervention targets for adoption and foster-care families. We discuss current difficulties in translating behavioural genetics research to prevention science, and provide recommendations to bridge the gap between behavioural genetics research and prevention science, with lessons for adoption and foster-care research and practice.

Early-Life Adversity and Blunted Stress Reactivity as Predictors of Alcohol and Drug use in Persons With COMT (rs4680) Val158Met Genotypes

BACKGROUND

Risk for alcoholism may be enhanced by exposure to early-life adversity (ELA) in persons with genetic vulnerabilities. We examined ELA in the presence of a common variant of the gene for the enzyme catechol-O-methyltransferase (COMT, Val158Met, rs4680) in relation to cortisol reactivity, the onset of early drinking, and experimentation with drugs.

METHODS

Saliva cortisol reactivity to speech and mental arithmetic stress was measured in 480 healthy young adults (23.5 years of age, 50% females) who experienced either 0, 1, or ≥ 2 forms of ELA during childhood and adolescence, provided information on use of alcohol and recreational drugs, and were genotyped for the Val158Met polymorphism.

RESULTS

ELA led to progressively smaller cortisol responses in the Met/Met and Val/Met allele groups but to progressively larger responses in Val homozygotes, F = 3.29, p = 0.011. ELA independently predicted earlier age at first drink, F = 14.2, p < 0.0001, with a larger effect in Met-allele carriers, F = 13.95, p < 0.00001, and a smaller effect in Val homozygotes, F = 4.14, p = 0.02. Similar effects were seen in recreational drug use. Cortisol reactivity was unrelated to drinking behavior or drug experimentation.

CONCLUSIONS

ELA leads to blunted stress reactivity and, independently, contributes to potentially risky drinking and drug-use behaviors in persons carrying 1 or 2 copies of the COMT 158Met allele. The results reinforce the impact of early experience on the stress axis and on risky behaviors, and they point to the 158Met allele as conveying a vulnerability to the early environment.

An acquired or heritable connective tissue disorder? A review of hypermobile Ehlers Danlos Syndrome

Hypermobile Ehlers Danlos Syndrome (hEDS) is a multifaceted disorder that is difficult to diagnose and manage primarily due to the unknown causes. Research on hEDS continues to evolve but tangible progress will be realized when the growing body of evidence compliments clinical practice. This critical review of the literature aims to stimulate lateral thinking about the pathogenesis, diagnosis and management of hEDS. The current international classification of Ehlers Danlos Syndrome introduced stricter diagnostic criteria for hEDS, which bore a blanket category (hypermobility spectrum disorders) for conditions presenting with symptomatic joint hypermobility, but do not match the hEDS diagnostic criteria. One would argue hEDS is another all-encompassing classification for heritable connective tissue disorders and or acquired musculoskeletal conditions without a definitive molecular basis. As scientific research progresses to accommodate validated and or annulled hypotheses, the plethora of unknowns in hEDS continue to challenge healthcare outcomes and care experiences.

It really does take a village: The role of neighbors in the etiology of nonaggressive rule-breaking behavior

Although there is growing recognition that disadvantaged contexts attenuate genetic influences on youth misbehavior, it is not yet clear how this dampening occurs. The current study made use of a "geographic contagion" model to isolate specific contexts contributing to this effect, with a focus on nonaggressive rule-breaking behaviors (RB) in the families' neighbors. Our sample included 847 families residing in or near modestly-to-severely disadvantaged neighborhoods who participated in the Michigan State University Twin Registry. Neighborhood sampling techniques were used to recruit neighbors residing within 5km of a given family (the mean number of neighbors assessed per family was 13.09; range, 1-47). Analyses revealed clear evidence of genotype-environment interactions by neighbor RB, such that sibling-level shared environmental influences on child RB increased with increasing neighbor self-reports of their own RB, whereas genetic influences decreased. Moreover, this moderation appeared to be driven by geographic proximity to neighbors. Sensitivity analyses further indicated that this effect was specifically accounted for by higher levels of neighbor joblessness, rather than elements of neighbor RB that would contribute to neighborhood blight or crime. Such findings provocatively suggest that future genotype-environment interactions studies should integrate the dynamic networks of social contagion theory.

Fluid Reasoning Mediates the Association of Birth Weight With ADHD Symptoms in Youth From Multiplex Families With ADHD

OBJECTIVE

We tested mediation of birth weight and ADHD symptoms by multiple biologically plausible neurocognitive functions and evaluated familiality of observed indirect effects.

METHOD

647 youth from 284 multiplex families with ADHD completed the Arithmetic, Digit Span, Vocabulary, and Block Design subtests of the Wechsler Intelligence Scale for Children (WISC). Multiple mediation tested WISC subtests as mediators of birth weight and multi-informant ADHD symptoms. Familiality of indirect effects was estimated via moderated mediation comparing conditional indirect effects across siblings concordant and discordant for ADHD.

RESULTS

Controlling for IQ and demographic factors, Arithmetic uniquely mediated birth weight and ADHD symptoms. Conditional indirect effects through Arithmetic did not differ across ADHD concordant and discordant siblings.

CONCLUSION

These cross-sectional findings support previous prospective longitudinal research implicating Arithmetic (i.e., fluid reasoning) as a preliminary causal mediator of birth weight and ADHD symptoms, and suggest that this pathway is independent of genetic influences on ADHD.

Gene–Environment Correlation in Humans: Lessons from Psychology for Quantitative Genetics

Evolutionary biologists have long been aware that the effects of genes can reach beyond the boundary of the individual, that is, the phenotypic effects of genes can alter the environment. Yet, we rarely apply a quantitative genetics approach to understand the causes and consequences of genetic variation in the ways that individuals choose and manipulate their environments, particularly in wild populations. Here, I aim to stimulate research in this area by reviewing empirical examples of such processes from the psychology literature. Indeed, psychology researchers have been actively investigating genetic variation in the environments that individuals experience—a phenomenon termed “gene–environment correlation” (rGE)—since the 1970s. rGE emerges from genetic variation in individuals’ behavior and personality traits, which in turn affects the environments that they experience. I highlight concepts and examples from this literature, emphasizing the relevance to quantitative geneticists working on wild, nonhuman organisms. I point out fruitful areas of crossover between these disciplines, including how quantitative geneticists can test ideas about rGE in wild populations.

PROSPER Intervention Effects on Adolescents' Alcohol Misuse Vary by GABRA2 Genotype and Age

Preventive intervention effects on adolescent alcohol misuse may differ based on genotypes in gene-by-intervention (G x I) interactions, and these G x I interactions may vary as a function of age. The current study uses a novel statistical method, time-varying effect modeling (TVEM), to test an age-varying interaction between a single nucleotide polymorphism in the GABRA2 gene (rs279845) and a preventive intervention in predicting alcohol misuse in a longitudinal study of adolescents (ages 11-20). The preventive intervention was PROSPER, a community-based system for delivery of family and school programs selected from a menu of evidence-based interventions. TVEM results revealed a significant age-varying GABRA2 x intervention interaction from ages 12 to 18, with the peak effect size seen around age 13 (IRR = 0.50). The intervention significantly reduced alcohol misuse for adolescents with the GABRA2 TT genotype from ages 12.5 to 17 but did not reduce alcohol use for adolescents with the GABRA2 A allele at any age. Differences in intervention effects by GABRA2 genotype were most pronounced from ages 13 to 16-a period when drinking is associated with increased risk for alcohol use disorder. Our findings provide additional evidence that intervention effects on adolescent alcohol misuse may differ by genotype, and provide novel evidence that the interaction between GABRA2 and intervention effects on alcohol use may vary with age. Implications for interventions targeting adolescent alcohol misuse are discussed.

Editorial: Closing in on causal links between environmental exposures and human development using observational data - "confound those confounders!"

A central goal of developmental psychopathology research is to understand the mechanisms linking environmental exposures in childhood to variations in mental health and development across the lifespan. The Journal of Child Psychology & Psychiatry has featured many influential studies and reviews addressing this important topic. This month's issue of the journal presents papers which address several specific environmental exposures, including prenatal factors, parenting and adverse childhood experiences, and illustrate important principles that should be used as a basis for taking the field forward.

Variation in the Heritability of Child Body Mass Index by Obesogenic Home Environment

Importance

The early obesogenic home environment is consistently identified as a key influence on child weight trajectories, but little research has examined the mechanisms of that influence. Such research is essential for the effective prevention and treatment of overweight and obesity.

Objective

To test behavioral susceptibility theory's hypothesis that the heritability of body mass index (BMI) is higher among children who live in more obesogenic home environments.

Design, Setting, and Participants

This study was a gene-environment interaction twin study that used cross-sectional data from 925 families (1850 twins) in the Gemini cohort (a population-based prospective cohort of twins born in England and Wales between March and December 2007). Data were analyzed from July to October 2013 and in June 2018.

Exposures

Parents completed the Home Environment Interview, a comprehensive measure of the obesogenic home environment in early childhood. Three standardized composite scores were created to capture food, physical activity, and media-related influences in the home; these were summed to create an overall obesogenic risk score. The 4 composite scores were split on the mean, reflecting higher-risk and lower-risk home environments.

Main Outcomes and Measures

Quantitative genetic model fitting was used to estimate heritability of age-adjusted and sex-adjusted BMI (BMI SD score, estimated using British 1990 growth reference data) for children living in lower-risk and higher-risk home environments.

Results

Among 1850 twins (915 [49.5%] male and 935 [50.5%] female; mean [SD] age, 4.1 [0.4] years), the heritability of BMI SD score was significantly higher among children living in overall higher-risk home environments (86%; 95% CI, 68%-89%) compared with those living in overall lower-risk home environments (39%; 95% CI, 21%-57%). The findings were similar when examining the heritability of BMI in the separate food and physical activity environment domains.

Conclusions and Relevance

These findings support the hypothesis that obesity-related genes are more strongly associated with BMI in more obesogenic home environments. Modifying the early home environment to prevent weight gain may be particularly important for children genetically at risk for obesity.

Effect of the interaction between oxytocin receptor gene polymorphism (rs53576) and stressful life events on aggression in Chinese Han adolescents

OBJECTIVES

Accumulating evidence suggests that stressful life events are associated with increased risk for aggressive behavior in adolescents; however, aggressive reactions to life stressors exhibit large individual differences. The present study sought to examine whether the interaction between a single nucleotide polymorphism (SNP [rs53576]) within the oxytocin receptor gene (OXTR) and stressful life events is related to aggression in Chinese Han adolescents.

METHODS

A total of 197 Chinese Han adolescents (14-17 years of age) were included in this study. Aggression was assessed using the 12-item short version of Buss and Perry Aggression Questionnaire. Stressful life events during the past 12 months were assessed using the Adolescent Self-Rating Life Events Checklist. Genomic DNA was extracted from saliva and buccal cells from each individual.

RESULTS

Multivariate analysis of variance yielded a significant interaction between OXTR rs53576 SNP and life stress (F = 2.449, p = 0.043, partial η2 = 0.051) and of sex × SNP × life stress (F = 3.144, p = 0.016, partial η2 = 0.064). High life stress during the past 12 months was associated with high levels of physical aggression and hostility in OXTR rs53576 homozygous AA adolescents but not in G-carrier adolescents. In boys, homozygous AA individuals in the high life stress group reported significantly higher levels of physical aggression than participants in the other three groups; the interaction, however, was not significant in girls.

CONCLUSIONS

This study, which analyzed a specific gene-environment interaction, demonstrated that AA OXTR rs53576 homozygosity may correlate with higher levels of aggression under high life stress conditions with a sample of healthy Chinese Han adolescents. These findings promote the etiological understanding of adolescent aggression, highlighting the complex effect of stressful life events on aggression, and adding evidence supporting the relationship between the oxytocin system and aggressive behavior in adolescents.

Motor dysfunction as research domain across bipolar, obsessive-compulsive and neurodevelopmental disorders

Although genuine motor abnormalities (GMA) are frequently found in schizophrenia, they are also considered as an intrinsic feature of bipolar, obsessive-compulsive, and neurodevelopmental disorders with early onset such as autism, ADHD, and Tourette syndrome. Such transnosological observations strongly suggest a common neural pathophysiology. This systematic review highlights the evidence on GMA and their neuroanatomical substrates in bipolar, obsessive-compulsive, and neurodevelopmental disorders. The data lends support for a common pattern contributing to GMA expression in these diseases that seems to be related to cerebello-thalamo-cortical, fronto-parietal, and cortico-subcortical motor circuit dysfunction. The identified studies provide first evidence for a motor network dysfunction as a correlate of early neurodevelopmental deviance prior to clinical symptom expression. There are also first hints for a developmental risk factor model of these mental disorders. An in-depth analysis of motor networks and related patho-(physiological) mechanisms will not only help promoting Research Domain Criteria (RDoC) Motor System construct, but also facilitate the development of novel psychopharmacological models, as well as the identification of neurobiologically plausible target sites for non-invasive brain stimulation.

Bayesian updating during development predicts genotypic differences in plasticity

Interactions between genotypes and environments are central to evolutionary genetics, but such interactions are typically described, rather than predicted from theory. Recent Bayesian models of development generate specific predictions about genotypic differences in developmental plasticity (changes in the value of a given trait as a result of a given experience) based on genotypic differences in the value of the trait that is expressed by naïve subjects. We used these models to make a priori predictions about the effects of an aversive olfactory conditioning regime on the response of Drosophila melanogaster larvae to the odor of ethyl acetate. As predicted, across 116 genotypes initial trait values were related to plasticity. Genotypes most strongly attracted to the odor of ethyl acetate when naïve reduced their attraction scores more as a result of the aversive training regime than those less attracted to the same odor when naïve. Thus, as predicted, the variance across genotypes in attraction scores was higher before than after the shared experience. These results support predictions generated by Bayesian models of development and indicate that such models can be successfully used to investigate how variation across genotypes in information derived from ancestors combines with personal experience to differentially affect developmental plasticity in response to specific types of experience.

Dating violence victimization and substance use: The role of a serotonin transporter gene polymorphism (5HTTLPR)

While there is developing research on how genes moderate the effect of stressful life events on substance use, the limited research has yet to focus on specific stressors. As adolescent dating violence victimization has been linked to various substance use behaviors, the current research seeks to further examine the longitudinal outcomes of adolescent dating violence victimization and the role that genes play in moderating these effects. Specifically, using data from the National Longitudinal Study of Adolescent to Adult Health (Add Health), a series of logistic and negative binomial regressions are run to analyze the direct and interactive effects of adolescent dating violence victimization and a polymorphism (5HTTLPR) in the promoter region of the serotonin transporter gene on both alcohol use problems and marijuana use. The results find that 5HTTLPR interacts with adolescent dating violence victimization to increase odds of marijuana use for the sample. However, the interaction between 5HTTLPR and adolescent dating violence has differential effects for males and females, suggesting sex differences regarding the susceptibility properties of 5HTTLPR. Implications of these findings are discussed.

Why does the magnitude of genotype-by-environment interaction vary?

Genotype-by-environment interaction (G × E), that is, genetic variation in phenotypic plasticity, is a central concept in ecology and evolutionary biology. G×E has wide-ranging implications for trait development and for understanding how organisms will respond to environmental change. Although G × E has been extensively documented, its presence and magnitude vary dramatically across populations and traits. Despite this, we still know little about why G × E is so evident in some traits and populations, but minimal or absent in others. To encourage synthetic research in this area, we review diverse hypotheses for the underlying biological causes of variation in G × E. We extract common themes from these hypotheses to develop a more synthetic understanding of variation in G × E and suggest some important next steps.

Do serum BDNF levels vary in self-harm behavior among adolescents and are they correlated with traumatic experiences?

The aim of this study was to compare serum brain-derived neurotrophic factor (BDNF) levels between adolescents that harm themselves, those that receive psychiatric treatment but do not harm themselves, healthy adolescents, and childhood traumas and to investigate the relationship between traumatic experiences and serum BDNF levels. The cases were divided into two groups of 40 adolescents exhibiting self-harm behavior (self-harm/diagnosed group) and 30 adolescents receiving psychiatric treatment but not exhibiting self-harm behaviors (non self-harm/diagnosed group). The control group (healthy control group) consisted of 35 healthy adolescents with no psychiatric disorders or self-harm behaviors. The adolescents were asked to fill in the Inventory of Statements About Self Injury (ISAS) and Childhood Trauma Questionnaire (CTQ). For BDNF measurement, blood samples were taken from the cases and controls. The serum BDNF level of self-harming adolescents who used the self-cutting method was significantly lower than that of other groups, and serum BDNF levels decreased with the increase in the emotional neglect and abuse severity of self-harming adolescents during childhood. In our study, serum BDNF levels decreased with the increase in emotional abuse in self-harming adolescents. This finding may indicate that neuroplasticity can be affected by a negative emotional environment during the early period.

A Concept Analysis of Resilience Integrating Genetics

Although clinicians and researchers are interested in the phenomenon of resilience, there is no agreed-upon definition of resilience. Scientific evidence suggests that resilience is influenced by intrapersonal (e.g. personality traits) and environmental (e.g. social support) variables. A concept analysis was conducted to better understand the meaning of resilience. In this analysis, the antecedent of resilience was a potentially traumatic event; the defining attributes were ego-resiliency, emotion regulation, social support, and heredity; and the consequences were none to mild psychopathological symptoms and positive adaptation. This analysis can help nurses better understand resilience and its relationships to both intrapersonal and environmental variables.

Genetic variants in 5-HTTLPR, BDNF, HTR1A, COMT, and FKBP5 and risk for treated depression after cancer diagnosis

BACKGROUND

The role of gene-environment interactions in the pathogenesis of depression is unclear. Previous studies addressed vulnerability for depression after childhood adversity and stressful life events among carriers of numerous specific genetic variants; however, the importance of individual genetic variants, the environmental exposures with which they interact, and the magnitude of the risk conveyed by these interactions remain elusive.

METHODS

We included 7,320 people with a first primary cancer identified in the prospective Diet, Cancer and Health study in an exposed-only cohort study. The mean age of the individuals was 68 years (5th, 95th percentiles: 58, 78) at cancer diagnosis. Using Cox regression models and cumulative incidence plots, we analyzed the associations between genetic variants in 5-HTTLPR, BDNF, HTR1A, COMT, and FKBP5 and use of antidepressants as well as hospital contact for depression after diagnosis of cancer.

RESULTS

Overall, we observed no statistically significant associations, with nonsignificant hazard ratio estimates for use of antidepressants of 0.95-1.07.

CONCLUSIONS

This study of elderly people indicates that it is unlikely that the investigated genetic variants are clinically relevantly associated with depression after diagnosis of cancer. The mechanisms for gene-environment interactions in younger individuals are probably different, and we advise caution in extrapolating our results to early life stress. However, conclusion from the present study might be generalizable to elderly persons exposed to other stressful life events.