Parenting and prenatal risk as moderators of genetic influences on conduct problems during middle childhood

Intergenerational transmission of comorbid internalizing and externalizing psychopathology at age 11: Evidence from an adoption design for general transmission of comorbidity rather than homotypic transmission

Psychopathology is intergenerationally transmitted through both genetic and environmental mechanisms via heterotypic (cross-domain), homotypic (domain-specific), and general (e.g., "p-factor") pathways. The current study leveraged an adopted-at-birth design, the Early Growth and Development Study (57% male; 55.6% White, 19.3% Multiracial, 13% Black/African American, 10.9% Hispanic/Latine) to explore the relative influence of these pathways via associations between adoptive caregiver psychopathology (indexing potential environmental transmission) and birth parent psychopathology (indexing genetic transmission) with adolescent internalizing and externalizing symptoms. We included composite measures of adoptive and birth parent internalizing, externalizing, and substance use domains, and a general "p-factor." Age 11 adolescent internalizing and externalizing symptom scores were the average of adoptive parent reports on the Child Behavior Checklist (n = 407). Examining domains independently without addressing comorbidity can lead to incorrect interpretations of transmission mode. Therefore, we also examined symptom severity (like the "p-factor") and an orthogonal symptom directionality score to more cleanly disentangle transmission modes. The pattern of correlations was consistent with mostly general transmission in families with youth showing comorbid internalizing and externalizing symptoms, rather than homotypic transmission. Findings more strongly supported potential environmental or evocative mechanisms of intergenerational transmission than genetic transmission mechanisms (though see limitations). Parent-specific effects are discussed.

Integrating the family stress model within a longitudinal sibling-adoption study of adolescent externalizing behavior

Using a sample of linked adopted children, adoptive and birth parents (N = 561), and biological siblings residing in the birth parent home (N = 191), we examined the role of genetics within family stress processes. We tested parental hostility (7 years) as a mediator of the associations between socioeconomic strain and rearing parent psychopathology (4 years) and adolescent externalizing behaviors (11 years) in adoptive and biological parent homes. Next, we examined parent social support (4 years) as a moderator of paths from socioeconomic strain and parent psychopathology to parental hostility. Parental hostility significantly mediated effects of socioeconomic strain and parent psychopathology on adolescent externalizing behaviors in biological and adoptive parent homes, respectively. Equivalence testing of the paths to adolescent externalizing behaviors across family types indicated a negligible role of passive gene-environment correlation. Parent social support significantly attenuated the effect of parent psychopathology on parental hostility in biological families. Birth parent externalizing behaviors were not significantly associated with adoptee externalizing behaviors nor adoptive parent hostility, suggesting negligible heritable risk or evocative gene-environment processes. Full- and half-sibling correlations indicated that children's unique rearing contexts contributed to the parenting they received and the externalizing behavior they exhibited. Implications for intervention are discussed.

Early risk for child externalising symptoms: Examining genetic, prenatal, temperamental and parental influences

This study utilized the Early Growth and Development Study (N = 561 adoptive children; 57.2% male, 55.3% White), a study of children adopted at birth, to examine heritable (birth parent psychopathology) and prenatal risk (prenatal maternal distress and smoking during pregnancy), infant negative affectivity, adoptive parent over-reactivity and warmth as independent predictors of childhood externalizing symptoms. The current study evaluated if: (1) infant negative affectivity and over-reactive parenting are candidate mediators for the effects of heritable and prenatal risk on externalizing symptoms and (2) parental warmth weakens the influence of heritable risk, prenatal risk, negative affectivity, and over-reactive parenting on externalizing symptoms. There were main effects of heritable risk, infant negative affectivity, and over-reactive parenting on child externalizing symptoms. The study found no support for the hypothesized mediation and moderation effects, suggesting that targeting parental over-reactivity rather than warmth would be more effective in reducing risk for childhood externalizing symptoms.

Examining timing effects in the intergenerational transmission of anxiety and depressive symptoms: A genetically informed study

The present study examined genetic, prenatal, and postnatal environmental pathways in the intergenerational transmission of anxiety and depressive symptoms from parents to early adolescents (when these symptoms start to increase), while considering timing effects of exposure to parent anxiety and depressive symptoms postnatally. The sample was from the Early Growth and Development Study, including 561 adopted children (57% male, 55% White, 13% Black/African American, 11% Hispanic/Latine, 20% multiracial, 1% other; 407 provided data in early adolescence) and their birth (BP) and adoptive parents (AP). Using a trait-state-occasion model with eight assessments from child ages 9 months to 11 years, we partitioned trait-like AP anxiety and depressive symptoms from time-specific fluctuations of AP anxiety and depressive symptoms. Offspring anxiety and depressive symptoms were assessed at 11 years (while controlling for similar symptoms at 4.5 years). Results suggested that time-specific fluctuations of AP1 (mostly mothers) anxiety/depressive symptoms in infancy (9 months) were indirectly associated with offspring anxiety/depressive symptoms at 11 years via offspring anxiety/depressive symptoms at 4.5 years; time-specific fluctuations of AP1 anxiety/depressive symptoms at child age 11 years were concurrently associated with offspring anxiety/depressive symptoms at 11 years. AP2 (mostly fathers) anxiety/depressive symptoms were not associated with offspring symptoms. Genetic and prenatal influences measured by BP internalizing problems were not associated with offspring symptoms. Results suggested infancy and early adolescence as developmental periods when children are susceptible to influences of parent anxiety and depressive symptoms. Preventive interventions should consider time-specific fluctuations in parent anxiety and depressive symptoms during these developmental periods. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Interactions Between Genetic, Prenatal Substance Use, Puberty, and Parenting are Less Important for Understanding Adolescents' Internalizing, Externalizing, and Substance Use than Developmental Cascades in Multifactorial Models

This study tested interactions among puberty-related genetic risk, prenatal substance use, harsh discipline, and pubertal timing for the severity and directionality (i.e., differentiation) of externalizing and internalizing problems and adolescent substance use. This is a companion paper to Marceau et al. (2021) which examined the same influences in developmental cascade models. Data were from the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort (n = 4504 White boys, n = 4287 White girls assessed from the prenatal period through 18.5 years). We hypothesized generally that later predictors would strengthen the influence of puberty-related genetic risk, prenatal substance use exposure, and pubertal risk on psychopathology and substance use (two-way interactions), and that later predictors would strengthen the interactions of earlier influences on psychopathology and substance use (three-way interactions). Interactions were sparse. Although all fourteen interactions showed that later influences can exacerbate or trigger the effects of earlier ones, they often were not in the expected direction. The most robust moderator was parental discipline, and differing and synergistic effects of biological and socially-relevant aspects of puberty were found. In all, the influences examined here operate more robustly in developmental cascades than in interaction with each other for the development of psychopathology and transitions to substance use.

Lifestyle Factors Counteract the Neurodevelopmental Impact of Genetic Risk for Accelerated Brain Aging in Adolescence

BACKGROUND

The transition from childhood to adolescence is characterized by enhanced neural plasticity and a consequent susceptibility to both beneficial and adverse aspects of one's milieu.

METHODS

To understand the implications of the interplay between protective and risk-enhancing factors, we analyzed longitudinal data from the Adolescent Brain Cognitive Development (ABCD) Study (n = 834; 394 female). We probed the maturational correlates of positive lifestyle variables (friendships, parental warmth, school engagement, physical exercise, healthy nutrition) and genetic vulnerability to neuropsychiatric disorders (major depressive disorder, Alzheimer's disease, anxiety disorders, bipolar disorder, schizophrenia) and sought to further elucidate their implications for psychological well-being.

RESULTS

Genetic risk factors and lifestyle buffers showed divergent relationships with later attentional and interpersonal problems. These effects were mediated by distinguishable functional neurodevelopmental deviations spanning the limbic, default mode, visual, and control systems. More specifically, greater genetic vulnerability was associated with alterations in the normative maturation of areas rich in dopamine (D2), glutamate, and serotonin receptors and of areas with stronger expression of astrocytic and microglial genes, a molecular signature implicated in the brain disorders discussed here. Greater availability of lifestyle buffers predicted deviations in the normative functional development of higher density GABAergic (gamma-aminobutyric acidergic) receptor regions. The two profiles of neurodevelopmental alterations showed complementary roles in protection against psychopathology, which varied with environmental stress levels.

CONCLUSIONS

Our results underscore the importance of educational involvement and healthy nutrition in attenuating the neurodevelopmental sequelae of genetic risk factors. They also underscore the importance of characterizing early-life biomarkers associated with adult-onset pathologies.

The pernicious role of stress on intergenerational continuity of psychopathology

Development and Psychopathology has been a premier resource for understanding stressful childhood experiences and the intergenerational continuity of psychopathology. Building on that tradition, we examined the unique and joint influences of maternal stress on children's effortful control (age 7) and externalizing behavior (age 11) as transmitted via genetics, the prenatal environment, and the postnatal environment. The sample included N = 561 adopted children and their biological and adoptive parents. Path models identified a direct effect of biological mother life stress on children's effortful control (β = -.08) and an indirect effect of her life stress on child externalizing behavior via effortful control (β = .52), but no main or indirect effects of biological parent psychopathology, prenatal stress, or adoptive mother adverse childhood experiences (ACES). Adoptive mother ACES amplified the association between biological mother life stress and child effortful control (β = -.08), externalizing behavior (β = 1.41), and the indirect effect via effortful control, strengthening associations when adoptive mothers reported average or high ACES during their own childhoods. Results suggest that novel study designs are needed to enhance the understanding of how life stress gets "under the skin" to affect psychopathology in the offspring of adults who have experienced stress.

Examination of promotive and protective effects on early adolescent prosocial behavior through a bioecological lens

Introduction

Prosocial behavior during childhood has been associated with numerous positive developmental and behavioral outcomes in adolescence and adulthood. Prosocial behavior, which includes cooperation and helping others, develops within a bioecological context. Considering it through such a lens enhances the understanding of the roles of different bioecological factors in its development.

Methods

Using data from a longitudinal study of adopted children and children reared with their biological parents, this paper examined if positive aspects of a child's bioecological system at age 7 predict prosocial behavior in early adolescence (age 11), and whether these bioecological factors could offset risk due to biological family psychopathology and/or maternal prenatal substance use. The analyses incorporated variables from different levels of Bronfenbrenner's bioecological model (the individual, microsystem, exosystem, and macrosystem) and examined the promotive, and potentially protective, effect of each contextual factor, while also considering their interplay with biological family psychopathology and prenatal substance use.

Results

Results from linear regression models indicated that the microsystem variable of parental warmth at age 7 had a promotive effect on age 11 prosocial behavior. Further, in addition to its main effect, parental warmth was protective against maternal substance use during pregnancy when children were raised with their biological parent (s). Household type (biological family) and biological family internalizing psychopathology were the only other significant predictors in the model, with each associated with lower prosocial behavior at age 11.

Discussion

Study results extend prior work on the benefits of parental warmth on child outcomes by employing a strength-based, bioecological approach to the development of prosocial behavior during early adolescence and examining "for whom" the effects of parental warmth are most protective.

Developmental trajectories of behavioral inhibition from infancy to age seven: The role of genetic and environmental risk for psychopathology

The present study leveraged data from a longitudinal adoption study of 361 families recruited between 2003 and 2010 in the United States. We investigated how psychopathology symptoms in birth parents (BP; Mage  = 24.1 years; 50.5-62.9% completed high school) and adoptive parents (AP; Mage  = 37.8 years; 80.9% completed college; 94% mother-father couples) influenced children's behavioral inhibition (BI) trajectories. We used latent growth models of observed BI at 18 and 27 months, and 4.5 and 7 years in a sample of adopted children (Female = 42%, White = 57%, Black = 11%, Multi-racial = 21%, Latinx = 9%). BI generally decreased over time, yet there was substantial variability in these trajectories. Neither BP nor AP psychopathology symptoms independently predicted systematic differences in BI trajectories. Instead, we found that AP internalizing symptoms moderated the effects of BP psychopathology on trajectories of BI, indicating a gene by environment interaction.

Overlapping brain correlates of superior cognition among children at genetic risk for Alzheimer's disease and/or major depressive disorder

Early life adversity (ELA) tends to accelerate neurobiological ageing, which, in turn, is thought to heighten vulnerability to both major depressive disorder (MDD) and Alzheimer's disease (AD). The two conditions are putatively related, with MDD representing either a risk factor or early symptom of AD. Given the substantial environmental susceptibility of both disorders, timely identification of their neurocognitive markers could facilitate interventions to prevent clinical onset. To this end, we analysed multimodal data from the Adolescent Brain and Cognitive Development study (ages 9-10 years). To disentangle genetic from correlated genetic-environmental influences, while also probing gene-adversity interactions, we compared adoptees, a group generally exposed to substantial ELA, with children raised by their biological families via genetic risk scores (GRS) from genome-wide association studies. AD and MDD GRSs predicted overlapping and widespread neurodevelopmental alterations associated with superior fluid cognition. Specifically, among adoptees only, greater AD GRS were related to accelerated structural maturation (i.e., cortical thinning) and higher MDD GRS were linked to delayed functional neurodevelopment, as reflected in compensatory brain activation on an inhibitory control task. Our study identifies compensatory mechanisms linked to MDD risk and highlights the potential cognitive benefits of accelerated maturation linked to AD vulnerability in late childhood.

Examining Research Domain Criteria (RDoC) constructs for anger expression and regulation in toddlers

The present study is focused on anger expression and regulation within the National Institute of Mental Health (NIMH) Research Domain Criteria (RDoC) construct of Frustrative Nonreward. Although previous studies have examined associations between child anger regulation and expression, these studies do not directly address the dynamic processes involved in Frustrative Nonreward using microlongitudinal methods. The current study used data from 561 adopted children, their adoptive parents, and birth parents and aimed to address gaps in the literature by examining: (a) temporal associations between anger expression during a frustrating situation, and behaviors thought to regulate emotions (e.g., attempt-to-escape, support-seeking, distraction, and focus-on-restraint) on a microlongitudinal scale during an arm restraint task assessed at 27 months; (b) birth parent externalizing problems and overreactive parenting by adoptive parents as predictors of child anger expression and moderators of the moment-to-moment associations estimated in Step 1; and (c) longitudinal associations (linear vs. quadratic) between anger expressions and externalizing behaviors at 4.5 years. Findings indicated that children's attempt-to-escape and support-seeking predicted an increase in anger expression in the following 3-s interval, whereas distraction and focus-on-restraint were not associated with changes in anger expression. Furthermore, we found that birth parents' externalizing problems were significantly associated with child anger expression, suggesting heritable influences. Anger expression showed a U-shaped longitudinal association with paternal report of externalizing behaviors at 4.5 years. Taken together, the findings emphasize the significance of integrating microlongitudinal analysis approaches into the RDoC framework, helping to advance our understanding of dynamic processes underlying reactions to Frustrative Nonreward. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Parenting in the Context of the Child: Genetic and Social Processes

The focus on the role of parenting in child development has a long-standing history. When measures of parenting precede changes in child development, researchers typically infer a causal role of parenting practices and attitudes on child development. However, this research is usually conducted with parents raising their own biological offspring. Such research designs cannot account for the effects of genes that are common to parents and children, nor for genetically influenced traits in children that influence how they are parented and how parenting affects them. The aim of this monograph is to provide a clearer view of parenting by synthesizing findings from the Early Growth and Development Study (EGDS). EGDS is a longitudinal study of adopted children, their birth parents, and their rearing parents studied across infancy and childhood. Families (N = 561) were recruited in the United States through adoption agencies between 2000 and 2010. Data collection began when adoptees were 9 months old (males = 57.2%; White 54.5%, Black 13.2%, Hispanic/Latinx 13.4%, Multiracial 17.8%, other 1.1%). The median child age at adoption placement was 2 days (M = 5.58, SD = 11.32). Adoptive parents were predominantly in their 30s, White, and coming from upper-middle- or upper-class backgrounds with high educational attainment (a mode at 4-year college or graduate degree). Most adoptive parents were heterosexual couples, and were married at the beginning of the project. The birth parent sample was more racially and ethnically diverse, but the majority (70%) were White. At the beginning of the study, most birth mothers and fathers were in their 20s, with a mode of educational attainment at high school degree, and few of them were married. We have been following these family members over time, assessing their genetic influences, prenatal environment, rearing environment, and child development. Controlling for effects of genes common to parents and children, we confirmed some previously reported associations between parenting, parent psychopathology, and marital adjustment in relation to child problematic and prosocial behavior. We also observed effects of children's heritable characteristics, characteristics thought to be transmitted from parent to child by genetic means, on their parents and how those effects contributed to subsequent child development. For example, we found that genetically influenced child impulsivity and social withdrawal both elicited harsh parenting, whereas a genetically influenced sunny disposition elicited parental warmth. We found numerous instances of children's genetically influenced characteristics that enhanced positive parental influences on child development or that protected them from harsh parenting. Integrating our findings, we propose a new, genetically informed process model of parenting. We posit that parents implicitly or explicitly detect genetically influenced liabilities and assets in their children. We also suggest future research into factors such as marital adjustment, that favor parents responding with appropriate protection or enhancement. Our findings illustrate a productive use of genetic information in prevention research: helping parents respond effectively to a profile of child strengths and challenges rather than using genetic information simply to identify some children unresponsive to current preventive interventions.

Examining reciprocal associations between parent depressive symptoms and child internalizing symptoms on subsequent psychiatric disorders: An adoption study

INTRODUCTION

The dynamic interplay between parent depressive symptoms and child internalizing behavior over time is not well understood.

METHODS

We used data from a prospective parent-offspring adoption design (N = 561) to examine associations between adoptive parent depressive symptoms and child internalizing behavior when children were ages 18 months, 27 months, 4.5 years, and 6 years, and subsequent child psychiatric disorder symptoms when children were between the ages of 6-8 years. Models also accounted for the contributions of birth parent psychopathology, birth mother depressive symptoms during pregnancy, and infant negative emotionality. Bidirectional associations between adoptive parent depressive symptoms and child internalizing behavior were examined using a random-intercept cross-lagged panel model.

RESULTS

There was evidence for associations between child internalizing behavior and adoptive parent depressive symptoms over time, with mothers' depressive symptoms being a more salient risk factor for child internalizing behavior than fathers'. We found one significant cross-lagged association from adoptive mother depressive symptoms at child age 18 months to child internalizing behavior at age 27 months. Infant negative emotionality (i.e., emotional liability) at age 9 months predicted both child internalizing behavior and adoptive parent depressive symptoms.

CONCLUSION

Results suggest that postnatal maternal depressive symptoms confer specific risks for child internalizing behaviors in toddlerhood and childhood and depressive symptoms in childhood.

Interactions between Genetic, Prenatal, Cortisol, and Parenting Influences on Adolescent Substance Use and Frequency: A TRAILS Study

INTRODUCTION

Dynamic relations between genetic, hormone, and pre- and postnatal environments are theorized as critically important for adolescent substance use but are rarely tested in multifactorial models. This study assessed the impact of interactions of genetic risk and cortisol reactivity with prenatal and parenting influences on both any and frequency of adolescent substance use.

METHODS

Data are from the TRacking Adolescents' Individual Lives Survey (TRAILS), a prospective longitudinal, multi-rater study of 2,230 Dutch adolescents. Genetic risk was assessed via 3 substance-specific polygenic scores. Mothers retrospectively reported prenatal risk when adolescents were 11 years old. Adolescents rated their parents' warmth and hostility at age 11. Salivary cortisol reactivity was measured in response to a social stress task at age 16. Adolescents' self-reported cigarette, alcohol, and cannabis use frequency at age 16.

RESULTS

A multivariate hurdle regression model showed that polygenic risk for smoking, alcohol, and cannabis predicted any use of each substance, respectively, but predicted more frequent use only for smoking. Blunted cortisol reactivity predicted any use and more frequent use for all 3 outcomes. There were 2 interactions: blunted cortisol reactivity exacerbated the association of polygenic risk with any smoking and the association of prenatal risk with any alcohol use.

CONCLUSION

Polygenic risk seems of importance for early use but less so for frequency of use, whereas blunted cortisol reactivity was correlated with both. Blunted cortisol reactivity may also catalyze early risks for substance use, though to a limited degree. Gene-environment interactions play no role in the context of this multifactorial model.

Childhood Antisocial Behavior: A Neurodevelopmental Problem

Early-onset disruptive, aggressive, and antisocial behavior is persistent, can become increasingly serious as children grow older, and is difficult to change. In 2007, our group proposed a theoretical model highlighting the interplay between neurobiological deficits and cognitive and emotional functioning as mediators of the link between genetic influences and early social adversity, on the one hand, and antisocial behavioral problems in childhood, on the other. In this article, we review the post-2007 evidence relevant to this model. We discuss research on genetics/epigenetics, stress/arousal regulation, and emotion and executive functioning in support of the argument that antisocial children, especially those who persist in engaging in antisocial behavior as they grow older, have a range of neuropsychological characteristics that are important in explaining individual differences in the severity and persistence of antisocial behavior. Current clinical practice tends not to acknowledge these individual neuropsychological risks factors or to target them for intervention. We argue that aggressive and disruptive behavior in childhood should be regarded as a neurodevelopmental problem and that intervening at the level of mediating neuropsychological processes represents a promising way forward in tackling these serious behavioral problems. Expected final online publication date for the Annual Review of Psychology, Volume 73 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Developmental Cascades from Polygenic and Prenatal Substance Use to Adolescent Substance Use: Leveraging Severity and Directionality of Externalizing and Internalizing Problems to Understand Pubertal and Harsh Discipline-Related Risk

The current study leveraged the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort (n = 4504 White boys, n = 4287 White girls assessed from the prenatal period through 18.5 years of age) to test a developmental cascade from genetic and prenatal substance use through pubertal timing and parenting to the severity of (regardless of type) and directionality (i.e., differentiation) of externalizing and internalizing problems to adolescent substance use. Limited associations of early pubertal timing with substance use outcomes were only observable via symptom directionality, differently for girls and boys. For boys, more severe exposure to prenatal substance use influenced adolescent substance use progression via differentiation towards relatively more pure externalizing problems, but in girls the associations were largely direct. Severity and especially directionality (i.e., differentiation towards relatively more pure externalizing problems) were key intermediaries in developmental cascades from parental harsh discipline with substance use progressions for girls and boys.

Birth Complications and Negative Emotionality Predict Externalizing Behaviors in Young Twins: Moderations with Genetic and Family Risk Factors

We examined interactions among genetic, biological, and ecological variables predicting externalizing behaviors in preschool and middle childhood. Specifically, we examined prediction of externalizing behaviors from birth complications and negative emotionality, each moderated by genetic risk for aggression and ecological risk factors of insensitive parenting and low family income. At ages 4 and 5 years, 170 twin pairs and 5 triplet sets (N = 355 children) were tested; 166 of those children were tested again at middle childhood (M = 7.9 years). Multilevel linear modeling results showed generally that children at high genetic risk for aggression or from low-income families were likely to have high scores on externalizing, but for children not at high risk, those with increased birth complications or more negative emotionality had high scores on externalizing. This study underscores the importance of considering biological variables as moderated by both genetic and ecological variables as they predict externalizing behaviors across early childhood.

Parental characteristics and offspring mental health and related outcomes: a systematic review of genetically informative literature

Various parental characteristics, including psychiatric disorders and parenting behaviours, are associated with offspring mental health and related outcomes in observational studies. The application of genetically informative designs is crucial to disentangle the role of genetic and environmental factors (as well as gene-environment correlation) underlying these observations, as parents provide not only the rearing environment but also transmit 50% of their genes to their offspring. This article first provides an overview of behavioural genetics, matched-pair, and molecular genetics designs that can be applied to investigate parent-offspring associations, whilst modelling or accounting for genetic effects. We then present a systematic literature review of genetically informative studies investigating associations between parental characteristics and offspring mental health and related outcomes, published since 2014. The reviewed studies provide reliable evidence of genetic transmission of depression, criminal behaviour, educational attainment, and substance use. These results highlight that studies that do not use genetically informative designs are likely to misinterpret the mechanisms underlying these parent-offspring associations. After accounting for genetic effects, several parental characteristics, including parental psychiatric traits and parenting behaviours, were associated with offspring internalising problems, externalising problems, educational attainment, substance use, and personality through environmental pathways. Overall, genetically informative designs to study intergenerational transmission prove valuable for the understanding of individual differences in offspring mental health and related outcomes, and mechanisms of transmission within families.

Disruptive Behavior in Siblings Discordant for Exposure to Maternal Smoking During Pregnancy: A Multi-rater Approach

INTRODUCTION

Maternal smoking during pregnancy (SDP) is associated with disruptive behavior. However, there is debate whether the SDP-disruptive behavior association is a potentially causal pathway or rather a spurious effect confounded by shared genetic and environmental factors.

AIMS AND METHODS

The Missouri Mothers and Their Children Study is a sibling comparison study that includes families (n = 173) selected for sibling pairs (aged 7-16 years) discordant for SDP. Critically, the sibling comparison design is used to disentangle the effects of SDP from familial confounds on disruptive behavior. An SDP severity score was created for each child using a combination of SDP indicators (timing, duration, and amount of SDP). Multiple informants (parents and teachers) reported on disruptive behavior (i.e., DSM-IV semi-structured interview, the Child Behavior Checklist, and Teacher Report Form).

RESULTS

The variability in disruptive behavior was primarily a function of within-family differences (66%-100%). Consistent with prior genetically informed approaches, the SDP-disruptive behavior association was primarily explained by familial confounds (genetic and environmental). However, when using a multi-rater approach (parents and teachers), results suggest a potentially causal effect of SDP on disruptive behavior (b = 0.09, SE = 0.04, p = 0.03). The potentially causal effect of SDP remained significant in sensitivity analyses.

DISCUSSION

These findings suggest that familial confounding likely plays a complex role in the SDP-disruptive behavior association when examining both parent and teacher reports of behavior. Importantly, the current study highlights the importance of multiple raters, reflecting a more comprehensive measure of complex behaviors (e.g., disruptive behavior) to examine the teratogenic effects of SDP.

IMPLICATIONS

Our study provides additional evidence that controlling for genetic and family factors is essential when examining the effect of SDP on later behavioral problems, as it explains a portion of the association between SDP and later behavioral problems. However, we found a significant association between SDP and disruptive behavior when using a multi-rater approach that capitalizes on both parent and teacher report, suggesting that parent and teacher ratings capture a unique perspective that is important to consider when examining SDP-behavior associations.

Child Effects on Parental Negativity: The Role of Heritable and Prenatal Factors

This study examined two possible mechanisms, evocative gene-environment correlation and prenatal factors, in accounting for child effects on parental negativity. Participants included 561 children adopted at birth, and their adoptive parents and birth parents within a prospective longitudinal adoption study. Findings indicated child effects on parental negativity, such that toddlers' negative reactivity at 18 months was positively associated with adoptive parents' over-reactive and hostile parenting at 27 months. Furthermore, we found that child effects on parental negativity were partially due to heritable (e.g., birth mother [BM] internalizing problems and substance use) and prenatal factors (e.g., BM illicit drug use during pregnancy) that influence children's negative reactivity at 18 months. This study provides critical evidence for "child on parent" effects.

The Early Growth and Development Study: A Dual-Family Adoption Study from Birth Through Adolescence

The Early Growth and Development Study (EGDS) is a prospective adoption study of birth parents, adoptive parents and adopted children (n = 561 adoptees). The original sample has been expanded to include siblings of the EGDS adoptees who were reared by the birth mother and assessed beginning at age 7 years (n = 217 biological children), and additional siblings in both the birth and adoptive family homes, recruited when the adoptees were 8-15 years old (n = 823). The overall study aims are to examine how family, peer and contextual processes affect child and adolescent adjustment, and to examine their interplay (mediation, moderation) with genetic influences. Adoptive and birth parents were originally recruited through adoption agencies located throughout the USA following the birth of a child. Assessments are ongoing and occurred in 9 month's intervals until the adoptees turned 3 years of age, and in 1 to 2 year intervals thereafter through age 15. Data collection includes the following primary constructs: child temperament, behavior problems, mental health, peer relations, executive functioning, school performance and health; birth and adoptive parent personality characteristics, mental health, health, context, substance use, parenting and marital relations; and the prenatal environment. Findings highlight the power of the adoption design to detect environmental influences on child development and provide evidence of complex interactions and correlations between genetic, prenatal environmental and postnatal environmental influences on a range of child outcomes. The study sample, procedures and an overview of findings are summarized and ongoing assessment activities are described.

Anxiety in the family: a genetically informed analysis of transactional associations between mother, father and child anxiety symptoms

BACKGROUND

Anxiety in parents is associated with anxiety in offspring, although little is known about the mechanisms underpinning these intergenerational associations. We conducted the first genetically sensitive study to simultaneously examine the effects of mother, father and child anxiety symptoms on each other over time.

METHOD

Adoptive parent and child symptoms were measured at child ages 6, 7 and 8 years from 305 families involved in the Early Growth and Development Study, using a prospective adoption design. Children were adopted at birth to nonrelatives, and composite data on internalising problems within birth families were used as a proxy measure of offspring inherited risk for anxiety. Structural equation models were fitted to the data to examine prospective associations between adoptive mother, father and child symptoms, whilst accounting for individuals' symptom stability over time.

RESULTS

Child anxiety symptoms at age 7 predicted adoptive mothers' anxiety symptoms at age 8. No mother-to-child or child-to-father effects were observed. These results were consistent in sensitivity analyses using only paternal offspring reports and using a second measure of child anxiety symptoms. Fathers' anxiety symptoms at child age 6 prospectively predicted child symptoms, but only when paternal offspring reports were included in the model. Composite data on birth family internalising problems were not associated with child anxiety symptoms.

CONCLUSIONS

Results show environmentally mediated associations between parent and child anxiety symptoms. Results support developmental theories suggesting that child anxiety symptoms can exert influence on caregivers, and mothers and fathers may play unique roles during the development of child symptoms. Further research is needed on the role of genetic transmission associated with anxiety symptoms in biologically related families. In the meantime, researchers and clinicians should strive to include fathers in assessments and consider the effects of child symptoms on caregivers.

Longitudinal examination of pathways to peer problems in middle childhood: A siblings-reared-apart design

To advance research from Dishion and others on associations between parenting and peer problems across childhood, we used a sample of 177 sibling pairs reared apart since birth (because of adoption of one of the siblings) to examine associations between parental hostility and children's peer problems when children were ages 7 and 9.5 years (n = 329 children). We extended conventional cross-lagged parent-peer models by incorporating child inhibitory control as an additional predictor and examining genetic contributions via birth mother psychopathology. Path models indicated a cross-lagged association from parental hostility to later peer problems. When child inhibitory control was included, birth mother internalizing symptoms were associated with poorer child inhibitory control, which was associated with more parental hostility and peer problems. The cross-lagged paths from parental hostility to peer problems were no longer significant in the full model. Multigroup analyses revealed that the path from birth mother internalizing symptoms to child inhibitory control was significantly higher for birth parent-reared children, indicating the possible contribution of passive gene-environment correlation to this association. Exploratory analyses suggested that each child's unique rearing context contributed to his or her inhibitory control and peer behavior. Implications for the development of evidence-based interventions are discussed.