Birth and Adoptive Parent Antisocial Behavior and Parenting: A Study of Evocative Gene-Environment Correlation.

Negative parenting is shaped by the genetically influenced characteristics of children (via evocative rGE) and by parental antisocial behavior; however, it is unclear how these factors jointly impact parenting. This study examined the effects of birth parent and adoptive parent antisocial behavior on negative parenting. Participants included 546 families within a prospective adoption study. Adoptive parent antisocial behavior emerged as a small but significant predictor of negative parenting at 18 months and of change in parenting from 18 to 27 months. Birth parent antisocial behavior predicted change in adoptive father's (but not mother's) parenting over time. These findings highlight the role of parent characteristics and suggest that evocative rGE effects on parenting may be small in magnitude in early childhood.

A constructive replication of the association between the oxytocin receptor genotype and parenting.

Behavioral genetic studies have robustly indicated that parenting behaviors are heritable-that is, individual differences in parenting are at least partially a function of genetic differences between persons. Few studies, however, have sought to identify the specific genetic variants that are associated with individual differences in parenting. Genes that influence the oxytocin system are of particular interest, given the growing body of evidence that points to the role of oxytocin for social behaviors, including parenting. The current study conducted examinations of associations between a variant in the oxytocin receptor gene (OXTR rs53576) and parental warmth, control, and negativity in a sample of 1,000 twin children and their parents (N = 500 families) from the Michigan State University Twin Registry to constructively replicate and extend prior work (Bakermans-Kranenburg & van IJzendoorn, 2008; Michalska et al., 2014). Analyses were conducted both at the level of the child and the level of the parent, allowing us to examine both child-driven (via evocative gene-environment correlation) and parent-driven genetic effects on parenting. Mothers' OXTR genotype predicted her warmth toward her children, even after controlling for child genotype. This association was not found for fathers. These findings add to the growing body of evidence linking oxytocin functioning to parental behavior and also highlight potential etiological differences in parenting across mothers and fathers.

Do non-shared environmental influences persist over time? An examination of days and minutes.

Non-shared environmental influences show only minimal stability over time prior to adulthood. The long assessment lags (typically 3-5 years) that characterize most longitudinal twin studies, however, make it difficult to interpret these results. To more rigorously evaluate non-shared environmental stability prior to adulthood, we fitted biometric correlated factors models to (1) seven consecutive days of self-reported negative and positive affect in 239 twin pairs aged 16-25 years and (2) seven consecutive minutes of observer rated warmth and control in 687 twin pairs aged 6-10 years. We then empirically examined patterns of etiologic stability over time using a mixed effects analog to the one-way ANOVA. Genetic and shared environmental correlations were found to be highly stable over both days and minutes. By contrast, non-shared environmental correlations decreased monotonically with increasing lag length, and moreover, were small-to moderate in magnitude when examining intervals longer than a few minutes. Such findings imply that the non-shared environment may be comprised primarily of transient and idiosyncratic effects prior to adulthood.

The etiology of the association between child antisocial behavior and maternal negativity varies across aggressive and non-aggressive rule-breaking forms of antisocial behavior.

There is a robust association between negative parenting and child antisocial behavior problems. However, the etiology of this association remains unclear. Extant literature has reported strikingly different conclusions across studies, with some highlighting genetic mediation and others highlighting environmental mediation. One possible reason for these discrepancies across studies may be the failure to differentiate between aggressive and non-aggressive (rule-breaking) dimensions of childhood antisocial behavior, given their notably different etiologies and developmental trajectories (Burt 2012). The current study sought to examine the phenotypic and etiologic associations of maternal negativity with aggressive and rule-breaking antisocial behavior, respectively. Participants included 824 mothers and their twin children between the ages of 6 and 10. Our results highlighted clear etiologic distinctions in the associations of aggression and rule-breaking with maternal negativity. Aggression was associated with maternal negativity via both genetic and environmental factors, whereas the association between non-aggressive rule-breaking and maternal negativity was entirely environmental in origin. These findings provide additional support for the presence of meaningful distinctions between aggressive and non-aggressive forms of antisocial behavior, and highlight the complex relationship between parenting and child outcome.

Evaluation of the known behavioral heterogeneity in conduct disorder to improve its assessment and treatment.

BACKGROUND: Conduct Disorder (CD) is among the most highly represented diagnostic problems in child and adolescent mental health treatment settings. There is a great deal of heterogeneity within the CD category, with potentially important implications for case conceptualization and treatment. The current review sought to detail forms of heterogeneity within CD, including callous-unemotional traits, comorbid Attention-Deficit Hyperactivity Disorder (ADHD), aggressive and nonaggressive antisocial behavior, and age of onset. METHODS: The current review summarizes research on etiological factors, correlates, and trajectories associated with distinguishable dimensions of CD, and considers how this heterogeneity should be incorporated into the assessment and treatment of CD. RESULTS: Callous-unemotional traits have been associated with a more severe and persistent form of CD, as have comorbid ADHD and child-onset CD. Aggressive antisocial behavior is a stable behavioral dimension that emerges in early childhood and is associated with high levels of neuroticism. Nonaggressive antisocial behavior demonstrates specific associations with impulsivity, is most frequent during adolescence, and evidences more moderate levels of stability. CONCLUSIONS: Conduct disorder is a highly heterogeneous disorder. Although the clinical implications of this heterogeneity are discussed, future research is clearly needed to shore up our understanding of the clinical ramifications of the sub-dimensions within CD.

Elucidating the etiology of individual differences in parenting: A meta-analysis of behavioral genetic research.

Decades of research have indicated the foundational importance of parenting to offspring outcomes during childhood and beyond. Unearthing the specific origins of parenting is therefore a critically important research objective. Extant research on this topic has suggested that parenting behaviors are multidetermined (Belsky, 1984) and are associated with a wide range of contextual and familial characteristics (e.g., ethnicity, community, family financial stress), as well as characteristics of the parents (e.g., personality) and their children (e.g., temperament). Behavioral genetic studies have further indicated that parenting behaviors are in fact heritable-that is, individual differences in parenting are at least partially a function of genetic differences between persons. Critically, however, the estimates of these genetic influences have varied dramatically across studies. It is also unclear how factors such as parent gender, child age, and methodological considerations may impact genetic influences on parenting behavior. In the current set of meta-analyses, we sought to quantitatively synthesize twin and adoption studies (n = 56) examining the etiology of parenting behavior, with the goal of more definitively cataloguing genetic and environmental effects on parenting. Results reveal significant effects of parental genetic makeup on parental behavior, but also highlight the genetic makeup of the child as a particularly prominent source of genetic transmission (via evocative gene-environment correlation). Environmental contributions to parenting also emerged as important, including both shared and nonshared environmental effects. Theoretical implications of these findings are discussed.

Maternal warmth and directiveness jointly moderate the etiology of childhood conduct problems.

BACKGROUND: Prior studies exploring gene-environment interactions (GxE) in the development of youth conduct problems (CP) have focused almost exclusively on single-risk experiences, despite research indicating that the presence of other risk factors and or the absence of protective factors can accentuate the influence of a given risk factor on CP. The goal of the current study was to fill this gap in the literature, evaluating whether risky and protective aspects of parenting might combine to jointly moderate the etiology of CP. METHODS: The sample consisted of 500 child twin pairs from the Michigan State University Twin Registry (MSUTR). Child CP was assessed using multiple informant reports. Maternal warmth and directiveness were assessed via videotaped dyadic interactions between mothers and each of their twins. RESULTS: Biometric GxE analyses revealed that directiveness and warmth did appear to jointly moderate the etiology of CP. In particular, shared environmental influences were accentuated by colder, less directive or 'less engaged' mothering, whereas genetic influences were strongest when the child was experiencing warmer, more directive or 'more authoritative' mothering. CONCLUSIONS: Such findings serve to highlight the synergistic effects of risky and protective experiences on child outcomes. They also provide additional empirical support for the bioecological form of GxE, which postulates that, in some cases, genetic influences may be most strongly expressed in the presence of low-risk environments.

Evocative gene-environment correlation in the mother-child relationship: a twin study of interpersonal processes.

The behavior genetic literature suggests that genetically influenced characteristics of the child elicit specific behaviors from the parent. However, little is known about the processes by which genetically influenced child characteristics evoke parental responses. Interpersonal theory provides a useful framework for identifying reciprocal behavioral processes between children and mothers. The theory posits that, at any given moment, interpersonal behavior varies along the orthogonal dimensions of warmth and control and that the interpersonal behavior of one individual tends to elicit corresponding or contrasting behavior from the other (i.e., warmth elicits warmth, whereas control elicits submission). The current study thus examined these dimensions of interpersonal behavior as they relate to the parent-child relationship in 546 twin families. A computer joystick was used to rate videos of mother-child interactions in real time, yielding information on mother and child levels of warmth and control throughout the interaction. Analyses indicated that maternal control, but not maternal warmth, was influenced by evocative gene-environment correlational processes, such that genetic influences on maternal control and child control were largely overlapping. Moreover, these common genetic influences were present both cross-sectionally and over the course of the interaction. Such findings not only confirm the presence of evocative gene-environment correlational processes in the mother-child relationship but also illuminate at least one of the specific interpersonal behaviors that underlie this evocative process.

The relationship between parent-child conflict and adolescent antisocial behavior: confirming shared environmental mediation.

Prior studies have indicated that the relationship between parent-child conflict and adolescent antisocial behavior is at least partially shared environmental in origin. However, all available research on this topic (to our knowledge) relies exclusively on parent and/or adolescent informant-reports, both of which are subject to various forms of rater bias. As the presence of significant shared environmental effects has often been attributed to rater bias in the past (Baker et al. Journal of Abnormal Psychology 16:219-235, 2007; Bartels et al. Journal of the American Academy of Child and Adolescent Psychiatry 42:1351-1359, 2003, Twin Research 7:162-175, 2004; Hewitt et al. Behavior Genetics 22:293-317, 1992), it would be important to confirm that findings of shared environmental mediation persist when even examining (presumably more objective) observer-ratings of these constructs. The current study thus examined the origins of the relationship between parent-child conflict and adolescent acting-out behavior, as measured using both observer-ratings and various informant-reports. Participants included 1,199 adopted and non-adopted adolescents in 610 families from the Sibling Interaction and Behavior Study (SIBS). Results indicated that parent-child conflict consistently predicts acting-out behavior in adopted adolescents, and moreover, that this association is equivalent to that in biologically-related adolescents. Most importantly, these findings did not vary across parent- and adolescent-reported or observer-ratings of parent-child conflict and acting-out behavior. Such findings argue strongly against rater bias as a primary explanation of shared environmental mediation of the association between parent-child conflict and adolescent antisocial behavior.

Confirming the etiology of adolescent acting-out behaviors: an examination of observer-ratings in a sample of adoptive and biological siblings.

BACKGROUND: A recent meta-analysis revealed moderate shared environmental influences (C) on most forms of child and adolescent psychopathology (Burt, 2009), including antisocial behavior. Critically, however, the research analyzed in this meta-analysis relied largely on specific informant-reports (and particularly parent and child reports), each of which is subject to various sources of rater bias. Observer-ratings of children's behaviors avoid many of these biases, and are thus well suited to verify the presence of C. Given this, we sought to buttress the evidence supporting C in two key ways. First, we sought to confirm that C contributes to observer-ratings in a sample of adoptive siblings, as similarity between adoptive siblings constitutes a 'direct' estimate of C. Second, we sought to confirm that these shared environmental influences persist across informants (i.e., the effects are not specific to the rater or the context in question). METHODS: The current study examined the etiology of observer-ratings of acting-out behaviors, as well as sources of etiological overlap across observer-ratings, adolescent self-report and maternal-report in sample of over 600 biological and adoptive sibling pairs from the Sibling Interaction and Behavior Study (SIBS). RESULTS: Results revealed moderate and significant shared environmental influences on observer-ratings (31%), as well as on the other informant-reports (20-23%). Moreover, a portion of these effects overlapped across measures (C correlations ranged from .32 to .34). CONCLUSIONS: Such findings argue against passive gene-environment correlations (rGE) and rater bias as primary explanations for earlier findings of C on antisocial behavior, and in this way, offer a critical extension of prior work indicating that the role of shared environmental influences on child and adolescent antisocial behavior was dismissed too soon.

The association between parent-child conflict and adolescent conduct problems over time: results from a longitudinal adoption study.

A handful of prior adoption studies have confirmed that the cross-sectional relationship between child conduct problems and parent-child conflict at least partially originates in the shared environment. However, as the direction of causation between parenting and delinquency remains unclear, this relationship could be better explained by the adolescent's propensity to elicit conflictive parenting, a phenomenon referred to as an evocative gene-environment correlation. In the current study, the authors thus examined the prospective relationship between conduct problems and parent-child conflict in a sample of adoptive families. Participants included 672 adolescents in 405 adoptive families assessed at 2 time points roughly 4 years apart. Results indicated that parent-child conflict predicts the development of conduct problems, whereas conduct problems do not predict increases in parent-child conflict. Such findings suggest that evocative gene-environment correlations are highly unlikely to be an explanation of prior shared environmental effects during adolescence. Moreover, because the adolescents in this study do not share genes with their adoptive parents, the association between conduct problems and parent-child conflict is indicative of shared environmental mediation in particular. Implications of the findings are discussed.