Sex differences in the genetic and environmental influences on childhood conduct disorder and adult antisocial behavior

Sex differences in the genetic and environmental influences on childhood conduct disorder and adult antisocial behavior were examined in a large community sample of 6,383 adult male, female, and opposite-sex twins. Retrospective reports of childhood conduct disorder (prior to 18 years of age) were obtained when participants were approximately 30 years old, and lifetime reports of adult antisocial behavior (antisocial behavior after 17 years of age) were obtained 8 years later. Results revealed that either the genetic or the shared environmental factors influencing childhood conduct disorder differed for males and females (i.e., a qualitative sex difference), but by adulthood, these sex-specific influences on antisocial behavior were no longer apparent. Further, genetic and environmental influences accounted for proportionally the same amount of variance in antisocial behavior for males and females in childhood and adulthood (i.e., there were no quantitative sex differences). Additionally, the stability of antisocial behavior from childhood to adulthood was slightly greater for males than females. Though familial factors accounted for more of the stability of antisocial behavior for males than females, genetic factors accounted for the majority of the covariation between childhood conduct disorder and adult antisocial behavior for both sexes. The genetic influences on adult antisocial behavior overlapped completely with the genetic influences on childhood conduct disorder for both males and females. Implications for future twin and molecular genetic studies are discussed.     

Deviant Peer Affiliation and Problem Behavior: A Test of Genetic and Environmental Influences

This study uses a multitrait, multimethod (MTMM) approach to investigate the genetic and environmental etiologies of childhood deviant peer affiliation (DPA) and problem behavior (PROB). The variability of genetic and environmental estimates by agent and method is also examined. A total of 77 monozygotic and 72 dizygotic twin pairs and each twin's close friend were assessed. The informants included parents, teachers, and twins, and the methods involved questionnaire reports and coder ratings of videotaped dyadic interactions between each twin and their close friend. Twin intraclass correlations and univariate models attributed DPA and PROB to genetic, and shared and nonshared environmental effects. Parameter estimates differed by rater and method, however. Results accentuate the imperative to attend to method effects inherent in MTMM behavioral geneticresearch.     

Differential Genetic and Environmental Influences on Reactive and Proactive Aggression in Children

While significant heritability for childhood aggression has been claimed, it is not known whether there are differential genetic and environmental contributions to proactive and reactive forms of aggression in children. This study quantifies genetic and environmental contributions to these two forms of aggression in an ethnically diverse urban sample of 9–10 year old twins (N = 1219), and compares results across different informants (child self-report, mother, and teacher ratings) using the Reactive–Proactive Aggression Questionnaire (RPQ). Confirmatory factor analysis of RPQ items indicated a significant and strong fit for a two-factor proactive–reactive model which was significantly superior to a one-factor model and which replicated across gender as well as the three informant sources. Males scored significantly higher than females on both self-report reactive and proactive aggression, findings that replicated on mother and teacher versions of the RPQ. Asian–Americans scored lower than most ethnic groups on reactive aggression yet were equivalent to Caucasians on proactive aggression. African–Americans scored higher than other ethnic groups on all measures of aggression except caregiver reports. Heritable influences were found for both forms of aggression across informants, but while boys’ self-reports revealed genetic influences on proactive (50%) and reactive (38%) aggression, shared and non-shared environmental influences almost entirely accounted for girls’ self-report reactive and proactive aggression. Although genetic correlations between reactive and proactive aggression were significant across informants, there was evidence that the genetic correlation was less than unity in boys self reported aggression, indicating that genetic factors differ for proactive and reactive aggression. These findings provide the first evidence for varying genetic and environmental etiologies for reactive and proactive aggression across gender, and provide additional support for distinction between these two forms of aggression.     

Personality in the age of industry: Structure,heritability, and correlates of personality in middle childhood from the perspective of parents,teachers, and children

Middle childhood is a crucial juncture in the lifespan where children work toward achieving a sense of competence foundational for future development. However, middle childhood has historically been underrepresented in the personality literature. The current study provides a comprehensive examination of personality in middle childhood using a large (N = 2510), longitudinal sample of 10- to 12-year-old twins. The structure, heritability, and correlates of personality in this period were investigated using personality ratings of parents, teachers, and children. Results showed that personality in middle childhood has a coherent structure, is heritable, and is relevant for developmentally salient outcomes such as externalizing behavior, substance use, and academic engagement. Results emphasize the importance of investigating personality in middle childhood across multiple informants.     

Relationships Between Parental Negativity and Childhood Antisocial Behavior over Time: A Bidirectional Effects Model in a Longitudinal Genetically Informative Design

This study examined the direction and etiology underlying the relationships between parental negativity and early childhood antisocial behavior using a bidirectional effects model in a longitudinal genetically informative design. We analyzed parent reports of parental negativity and early childhood antisocial behavior in 6,230 pairs of twins at 4 and 7 years of age. Results from a cross-lagged twin model contribute to the understanding of the mechanisms underlying the bidirectional processes involved in parental negativity and childhood antisocial behavior. Specifically, the findings of this study suggest that the association between parenting and child antisocial behavior is best explained by both parent-driven and child-driven effects. We found support for the notion that parent's negative feelings towards their children environmentally mediate the risk for child antisocial behavior. We also found evidence of genetically mediated child effects; in which genetically influenced antisocial behavior evoke parental negativity towards the child.     

Religiousness, antisocial behavior, and altruism: genetic and environmental mediation

Although religiousness is considered a protective factor against antisocial behaviors and a positive influence on prosocial behaviors, it remains unclear whether these associations are primarily genetically or environmentally mediated. In order to investigate this question, religiousness, antisocial behavior, and altruistic behavior were assessed by self-report in a sample of adult male twins (165 MZ and 100 DZ full pairs, mean age of 33 years). Religiousness, both retrospective and current, was shown to be modestly negatively correlated with antisocial behavior and modestly positively correlated with altruistic behavior. Joint biometric analyses of religiousness and antisocial behavior or altruistic behavior were completed. The relationship between religiousness and antisocial behavior was due to both genetic and shared environmental effects. Altruistic behavior also shared most all of its genetic influence, but only half of its shared environmental influence, with religiousness.     

Reactive vs. proactive antisocial behavior: differential correlates of child ADHD symptoms?

This study examines the relation between proactive and reactive antisocial behavior with Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms. Caregivers of children aged 8 to 15 (n = 84) being evaluated at a child psychiatry outpatient clinic served as participants. Given the conceptual similarity between reactive antisocial behavior (ASB) and particular ADHD symptoms, we hypothesized that ADHD symptoms would be more closely related to reactive than to proactive ASB. Based on peer deviancy training models of ASB, we also hypothesized that the relation between ADHD symptoms and proactive ASB would increase from middle childhood to adolescence. Both hypotheses were supported. These findings suggest that reactive ASB is relatively specific to ADHD symptoms, and that intervening before early adolescence may be critical to prevent the onset of comorbid proactive ASB.     

Deviant Peer Affiliation and Antisocial Behavior: Interaction with Monoamine Oxidase A (MAOA) Genotype

Although genetic and environmental factors are separately implicated in the development of antisocial behavior (ASB), interactive models have emerged relatively recently, particularly those incorporating molecular genetic data. Using a large sample of male Caucasian adolescents and young adults from the National Longitudinal Study of Adolescent Health (Add Health), the association of deviant peer affiliation, the 30-base pair variable number tandem repeat polymorphism in promoter region of the monoamine oxidase-A (MAOA) gene, and their interaction, with antisocial behavior (ASB) was investigated. Weighted analyses accounting for over-sampling and clustering within schools as well as controlling for age and wave suggested that deviant peer affiliation and MAOA genotype were each significantly associated with levels of overt ASB across a 6-year period. Only deviant peer affiliation was significantly related to covert ASB, however. Additionally, there was evidence suggestive of a gene-environment interaction (G × E) where the influence of deviant peer affiliation on overt ASB was significantly stronger among individuals with the high-activity MAOA genotype than the low-activity genotype. MAOA was not significantly associated with deviant peer affiliation, thus strengthening the inference of G × E rather than gene-environment correlation (rGE). Different forms of gene-environment interplay and implications for future research on ASB are discussed.     

The etiology of behavioral problems and competencies in very young twins

Although genetic and environmental influences on behavior problems in middle childhood and adolescence have been well-studied, little is known about the etiology of behavior problems in very early childhood. The present study explores genetic and environmental contributions to individual differences in behavior problems and competences in an infant-toddler sample of twins. There were 1,950 twin pairs (mean age=23.8 months) who were rated by parents on the Infant-Toddler Social and Emotional Assessment. All four domains (Externalizing, Internalizing, Dysregulation, Competence) and 20 subscales-indices on the Infant-Toddler Social and Emotional Assessment displayed significant heritability. There were also substantial shared environmental influences operating on most of the domains and subscales. Compared with behavior problems, behavioral competencies were less heritable and more influenced by shared environments.     

The Etiology of Behavior Problems in 7-Year-Old Twins: Substantial Genetic Influence and Negligible Shared Environmental Influence for Parent Ratings and Ratings by Same and Different Teachers

Parent ratings of behavior problems in childhood show substantial genetic influence and modest shared environmental influence. However, few studies have compared these results to teacher ratings and no previous studies have compared same-teacher ratings to different-teacher ratings. 3,714 7-year-old twin pairs in the Twins Early Development Study were rated by parents and teachers on the Strengths and Difficulties Questionnaire. Substantial heritability and negligible shared environmental influence were found for data from all three raters for total behavior problems, hyperactivity, prosocial behavior, peer problems, conduct problems, and emotional symptoms. Sex-limitation models revealed similar results for males and females, although there was some evidence for greater heritability for boys, especially when twins were rated by the same teacher.     

Preliminary evidence that specific candidate genes are associated with adolescent-onset antisocial behavior

Though initially conceptualized as resulting from peer imitation of child-onset or life-course-persistent youth [Moffitt, 1993], there is mounting evidence from twin studies that adolescent-onset or adolescent-limited antisocial behavior may also be genetically influenced. This study sought to provide preliminary molecular genetic evidence in support of these findings. We further evaluated whether genetic associations varied between behavioral subtypes of ASB (i.e., physical aggression and nonaggressive rule-breaking), given that only the latter has been found to characterize adolescent-onset ASB. The sample consisted of 211 undergraduate men of European-American ancestry. Three polymorphisms with theoretical and/or empirical ties to ASB or related traits (i.e., tryptophan hydroxylase-A218C, 5HT(2A) His452Tyr, and the DAT1 variable nucleotide tandem repeat) were genotyped. Analyses revealed that two of the three polymorphisms (i.e., His452Tyr and DAT1) were associated with adolescent ASB. Moreover, these associations appeared to be specific to the nonaggressive, rule-breaking form of ASB, and did not extend to physical aggression, further supporting ties to adolescent ASB in particular. Such results thus constructively replicate earlier findings of genetic influence on adolescent ASB. They also offer preliminary evidence that the genetic processes underlying aggressive and nonaggressive antisocial behavior may be (at least partially) distinct.     

Adolescent Self-Regulation as Resilience: Resistance to Antisocial Behavior within the Deviant Peer Context

This study tests the hypothesis that self-regulation serves as a resiliency factor in buffering youth from negative influences of peer deviance in middle to late adolescence. The interactive effects between peer deviance and self-regulation were investigated on change in antisocial behavior from age 17 to 19 years in an ethnically diverse sample of adolescents. A multi-agent construct was created using adolescent, parent, and teacher reports of self-regulation and peer deviance. Results indicated that self-regulation shows convergent validity and covaries as expected with developmental patterns of adolescent antisocial behavior. Self-regulation moderated the association of peer deviance with later self-reported adolescent antisocial behavior after controlling for prior levels of antisocial behavior. The implications of these findings for models for the development of antisocial behaviors and for intervention science are discussed.     

Impulsive corporal punishment by mothers and antisocial behavior and impulsiveness of children

This study tested the hypothesis that corporal punishment (CP), such as spanking or slapping a child for purposes of correcting misbehavior, is associated with antisocial behavior (ASB) and impulsiveness by the child. The data were obtained through interviews with a probability sample of 933 mothers of children age 2–14 in two small American cities. Analyses of variance found that the more CP experienced by the child, the greater the tendency for the child to engage in ASB and to act impulsively. These relationships hold even after controlling for family socioeconomic status, the age and sex of the child, nurturance by the mother, and the level of non-corporal interventions by the mother. There were also significant interaction effects of CP with impulsiveness by the mother. When CP was carried out impulsively, it was most strongly related to child impulsiveness and ASB; when CP was done when the mother was under control, the relationship to child behavior problems was reduced but still present. ln view of the fact that there is a high risk of losing control when engaged in CP, even by parents who are not usually impulsive, and the fact that impulsive CP is so strongly associated with child behavior problems, the results of this study suggest that CP is an important risk factor for children developing a pattern of impulsive and antisocial behavior which, in turn, may contribute to the level of violence and other crime in society. © 1998 John Wiley & Sons, Ltd.     

Prosocial behavior from early to middle childhood: genetic and environmental influences on stability and change

Prosocial behavior is important for the functioning of society. This study investigates the extent to which environment shared by family members, nonshared environment, and genetics account for children's prosocial behavior. The prosocial behavior of twins (9,424 pairs) was rated by their parents at the ages of 2, 3, 4, and 7 and by their teachers at age 7. For parent ratings, shared environmental effects decreased from .47 on average at age 2 to .03 at age 7, and genetic effects increased from .32 on average to .61. The finding of weak shared environmental effects and large heritability at age 7 was largely confirmed through the use of teacher ratings. Using longitudinal genetic analyses, the authors conclude that genetic effects account for both change and continuity in prosocial behavior and nonshared environment contributes mainly to change.     

The Genetic and Psychophysiological Basis of Antisocial Behavior: Implications for Counseling and Therapy

The notion that crime may have a genetic and biological basis has been resisted due to the assumption that this view necessitates a deterministic attitude to crime. This article argues that this assumption is unwarranted, and that an understanding of the genetic and psychophysiological basis of crime and antisocial behavior has important implications for counselors dealing with antisocial individuals. The interaction between genetic and environmental factors suggests that environmental changes may reduce the expression of any genetic predisposition. Psychophysiological factors interact with social factors in producing antisocial behavior, and recent psychophysiological studies have identified enhanced attentional ability in antisocial individuals that can be capitalized on by counselors in diverting clients from an antisocial way of life.     

Antisocial Behavior: Exploring Behavioral,Cognitive, and Environmental Influences on Expulsion

We investigated the role of three significant potential contributors to antisocial behavior (ASB)—behavior, cognitive, and environmental influences—and their impact on expulsion. The following measures were administered to a community sample of antisocial adolescents: nonverbal ability and working memory, behavioral profile (rated by the social worker and self‐rated), and environmental background (socio‐economic background and family structure). The data indicated that their working memory performance was in the average range; however, group means were significantly lower in the nonverbal ability test. Although social workers' assessments of the adolescents' behavior were closely related to their self‐reports, it was the latter that was best able to correctly classify those who had been expelled from their non‐expelled ASB peers. Environmental background did not appear to have a strong role in expulsion rates. The results are discussed in the context of persistency of ASB and ways forward to provide support and intervention for adolescents. Copyright © 2013 John Wiley & Sons, Ltd.     

The heritability of attitudes: a study of twins.

The genetic basis of individual differences in attitudes was examined in a survey of 195 pairs of monozygotic twins and 141 pairs of same-sex dizygotic twins. A principal components analysis of the 30 attitude items in the survey identified 9 attitude factors, of which 6 yielded significant heritability coefficients. Nonshared environmental factors accounted for the most variance in the attitude factors. Possible mediators of attitude heritability were also assessed, including personality traits, physical characteristics, and academic achievement. Analyses showed that several of these possible mediators correlated at a genetic level with the heritable attitude factors, suggesting that the heritability of the mediator variables might account for part of the heritable components of some attitudes. There was also some evidence that highly heritable attitudes were psychologically "stronger" than less heritable attitudes.     

Significance of Childhood Conduct Problems to Later Development of Conduct Disorder Among Children With ADHD: A Prospective Follow-Up Study

This study investigates whether low to moderate levels of childhood oppositional defiant disorder (ODD) and conduct disorder (CD) behaviors contribute to the development of clinically diagnosed CD in adolescence, in children with attention deficit hyperactivity disorder (ADHD). Participants were 207 White boys (ages 6-12) with ADHD free of conduct disorder diagnoses. Parent and teacher ratings were obtained. Participants were assessed at mean age 18 by clinicians blind to childhood status. A non-ADHD group (recruited in adolescence) was also studied. ODD behavior ratings did not predict CD in adolescence, whereas CD behavior ratings did. No single ODD or CD behavior predicted adolescent outcome. ADHD probands with very low ratings (Not at all, Just a little) by parents and teachers on all CD behaviors were still at significantly increased risk for CD in adolescence, compared to non-ADHD controls. The same relationships were found between childhood ODD and CD behaviors, and antisocial personality disorder in adulthood (mean age, 25). We conclude that childhood ADHD is a developmental precursor of later antisocial disorder, even in the absence of comorbid ODD or CD in childhood. However, low levels of CD-type problems are not innocuous, because they predict later CD among children with ADHD without comorbid CD.     

Synergistic interaction of child manageability problems and parent-discipline tactics in predicting future growth in externalizing behavior for boys.

Manageability problems during early childhood for boys were hypothesized to disrupt parental discipline practices. In turn, disrupted parental discipline practices were hypothesized to interact with manageability problems during late childhood to predict change in antisocial behavior during the transition from elementary to middle school. Results indicated that maternal retrospective perceptions of unmanageability predicted observed maternal discipline practices, even when maternal antisocial behavior and depressed mood and the disruptive and antisocial behavior of the boy were statistically controlled. Graphical analyses and latent class growth models indicated that level of temper tantrums interacted with maternal discipline in predicting change in teacher ratings of antisocial behavior. The nature of the interaction indicated that maternal discipline was a risk factor for growth in antisocial behavior only for boys with high levels of tantrums.     

Examining transactional influences between reading achievement and antisocially-behaving friends

The association between poorer academic outcomes and having antisocial friends is reliably demonstrated yet not well understood. Genetically sensitive designs uniquely allow for measuring genetic vulnerabilities and/or environmental risk in the association of antisocial friend behavior and poor school achievement, allowing for a better understanding of the nature of the association. This study included 233 pairs of twins from the Florida Twin Project on Reading. First, the role of antisocial friends as an environmental moderator of reading comprehension was examined. Antisocial friends significantly moderated the nonshared environmental variance in reading comprehension, with increased variation at lower levels of association with antisocial friends, with niche-picking indicated. Second, the role of reading comprehension as an environmental moderator of antisocial friends was examined. Reading comprehension significantly moderated the nonshared environmental variance in associating with antisocial friends, with increased variance at lower levels of reading comprehension and indication that common genetic influences contributed to higher reading achievement and better-behaved friends. In total, these results suggested reciprocal influences between reading achievement and antisocially-behaving friends. The impact of antisocial friends appeared to be limited in the extent to which they can undermine reading achievement, and high reading achievement appeared to support less association with antisocial friends.