Daniel Pérusse

• Université de Montréal

This paper is a revised and updated edition of a previous description of the Quebec Newborn Twin Study (QNTS), an ongoing prospective longitudinal follow-up of a birth cohort of twins born between 1995 and 1998 in the greater Montreal area, Québec, Canada. The goal of QNTS is to document individual differences in the cognitive, behavioral, and soci...

We used magnetic resonance (MR) images obtained in same-sex and opposite-sex dizygotic twins (n = 119, 8 years of age) to study possible effects of prenatal androgens on craniofacial features. Using a principal component analysis of 19 craniofacial landmarks placed on the MR images, we identified a principal component capturing craniofacial feature...

Little empirical evidence exists on the comparability of heart rate variability (HRV) quantification methods commonly used in infants. The aim was to compare three methods of HRV estimation: (1) fast Fourier transform (FFT), (2) autoregressive (AR), and (3) the Porges methods. HRV was estimated in 63 healthy 5-month-old infants. HRV parameters were...

Eating behaviors during childhood are related both to children's diet quality and to their weight status. A better understanding of the determinants of eating behavior during childhood is essential for carrying out effective dietary interventions. We assessed the contribution of genetic and environmental factors to variations in selected eating beh...

This study examined whether (a) a genetic disposition for physical health problems increases the risk of peer victimization and (b) peer victimization interacts with genetic vulnerability in explaining physical health problems. Participants were 167 monozygotic and 119 dizyogtic twin pairs. Physical symptoms were assessed in early childhood and ear...

Background: Few twin studies have examined nutrition-related phenotypes among children, and none has investigated energy and macronutrient intakes. Objective: The objective was to quantify genetic and environmental influences on variations in energy and macronutrient intakes among children aged 9 years. Design: We conducted a nutrition study a...

Objectives: To determine the relative contributions of genetic and environmental factors on daytime and nighttime continuous sleep duration at 6, 18, 30, and 48 months of age, and to identify different subgroups of children who followed different daytime and nighttime sleep duration trajectories and to investigate their etiology. Methods: The cu...

This study assessed the genetic and environmental contributions to peer difficulties in the early school years. Twins' peer difficulties were assessed longitudinally in kindergarten (796 twins, M(age) = 6.1 years), Grade 1 (948 twins, M(age) = 7.1 years), and Grade 4 (868 twins, M(age) = 10 years) through multiple informants. The multivariate resul...

The Quebec Newborn Twin Study (QNTS) is an ongoing prospective longitudinal follow-up of a birth cohort of twins born between 1995 and 1998 in the greater Montreal area, Québec, Canada. The goal of QNTS is to document individual differences in the cognitive, behavioral, and social-emotional aspects of developmental health across childhood, their ea...

Cortical surface area has been largely overlooked in genetic studies of human brain morphometry, even though phylogenetic differences in cortical surface area between individuals are known to be influenced by differences in genetic endowment. In this study, we examined the relative contribution of genetic and environmental influences on cortical su...

The goal of this study is twofold: (1) to assess brain anatomical differences between children meeting diagnostic criteria for oppositional defiant disorder (ODD) and healthy controls, and (2) to investigate whether morphological brain characteristics associated with ODD differ in boys and girls. Eight-year-old participants (N = 38) were scanned us...

To examine the genetic and environmental influences on variances in weight, height, and BMI, from birth through 19 years of age, in boys and girls from three continents. Cross-sectional twin study. Data obtained from a total of 23 twin birth-cohorts from four countries: Canada, Sweden, Denmark, and Australia. Participants were Monozygotic (MZ) and...

Mean and Standard Error of weight (kg) in MZ and DZ twins of four countries, from birth through 19 years of age. (PDF)

Mean and Standard Error of height (m) in MZ and DZ twins of four countries, from birth through 19 years of age. (PDF)

Mean and Standard Error of BMI (kg/m2) in MZ and DZ twins of four countries, from birth through 19 years of age. (PDF)

Intra-class correlations (ICC) between MZ and DZ twin pairs for mean weight (kg), height (m), and BMI (kg/m2), from birth through 19 years of age. (PDF)

Sample sizes and characteristics of the cohorts included in the analyses. (PDF)

Aggressive behavior in middle childhood is at least partly explained by genetic factors. Nevertheless, estimations of simple effects ignore possible gene-environment interactions (G × E) or gene-environment correlations (rGE) in the etiology of aggression. The present study aimed to simultaneously test for G × E and rGE processes between aggression...

CREB1 has previously been implicated in mood disorders, suicide, and antidepressant response. There is some evidence that the T allele in rs4675690, a single-nucleotide polymorphism near the CREB1 gene, is involved in the modulation of neural responses to negative stimuli. It is not known whether differential brain activity during negative mood sta...

Our aims were to (1) examine possible neuroanatomical abnormalities associated with the Disruptive Behavior Disorders (DBDs) as a group and (2) assess neuroanatomical anomalies specific to each DBD (i.e., conduct disorder [CD] and oppositional defiant disorder). Cortical thickness analysis and voxel-based morphometry were analyzed in 47 8-year-old...

Glucocorticoids (GCs) have been related to social rank in many studies across species, a particular rank giving rise to a particular stress-related physiological profile. Our aim was to examine the hypothesis that GCs levels in toddlers would be related to social dominance in a competitive resource situation. Subjects were 376 toddlers from the Que...

Early exposure to stress and teratogenic substances have an impact on brain structures involved in cognition and mental health. While moderate-to-high levels of prenatal alcohol exposure (PAE) have repeatedly been associated with long-term neurodevelopmental deficits, no consensus has yet been reached on the detrimental effects of low-to-moderate P...

Disregard for rules, a key component of oppositional defiant and conduct disorders, is stable during early childhood. This study investigates for the first time the relative importance of genetic and environmental factors underlying this early developmental stability. Maternal reports of child disregard for rules were obtained at four time points f...

This study used the monozygotic (MZ) twin difference method to examine whether differences in friends' aggression increased the differences in MZ twins' aggression and depressive symptoms from kindergarten to Grade 1 and whether perceived victimization by the friend played a mediating role in this context. Participants were 223 MZ twin pairs. Resul...

Twin studies are one of the most powerful study designs for estimating the relative contribution of genetic and environmental influences on phenotypic variation inhuman brain morphology. In this study, we applied deformation based morphometry, a technique that provides a voxel-wise index of local tissue growth or atrophy relative to a template brai...

Healthy adults carrying the short (S) allele of the human serotonin transporter gene linked polymorphism (5-HTTLPR) show increased amygdala activation during visual processing of emotionally negative stimuli compared to healthy adults homozygous for the long (L) allele. To determine whether abnormal brain responses during negative emotion appear ea...

It has been increasing rapidly interest in understanding genetic effects on brain structure and function in recent years. In this study, we examined the genetic and environmental influences on the variation in cortical thickness and specific tissue volumes in a large cohort of 8-year-old healthy twins. The present study can provide a better estimat...

This study investigated the relation between theory of mind and reactive and proactive aggression, respectively, as well as the moderating role of peer victimization in this context. The 574 participants were drawn from a longitudinal study of twins. Theory of mind was assessed before school entry, when participants were 5 years old. Reactive and p...

The present study examined the association between theory of mind and indirect versus physical aggression, as well as the potential moderating role of prosocial behavior in this context. Participants were 399 twins and singletons drawn from two longitudinal studies in Canada. At five years of age, children completed a theory of mind task and a rece...

Genetic risk for depressive behavior may increase the likelihood of exposure to environmental stressors (gene-environment correlation, rGE). By the same token, exposure to environmental stressors may moderate the effect of genes on depressive behavior (gene-environment interaction, GxE). Relating these processes to a peer-related stressor in childh...

Home environment quality is a well-known predictor of school readiness (SR), although the underlying processes are little known. This study tested two hypotheses: (a) child language mediates the association between home characteristics (socioeconomic status and exposure to reading) and SR, and (b) genetic factors partly explain the association betw...

The present study investigated the “template effect” on the morphometric analysis of a pediatric brain MRI database obtained from 8-year-old children through various measures of surface and volumetric morphologies. We first constructed an age-appropriate template from an independent set of pediatric brain images and then compared it with a well-kno...

There is growing evidence that genetic factors are involved in the occurrence of sleep terrors. Twin studies provide invaluable information regarding genetic and environmental factors that can affect the manifestation of the disease; however, most previous twin studies on sleep terrors were performed retrospectively or with a sample that was too sm...

Attention deficit hyperactivity disorder (ADHD) is the most prevalent psychiatric disorder emerging during childhood. Psychostimulant medications (e.g., methylphenidate) noticeably reduce ADHD symptoms in most children. Since methylphenidate inhibits dopamine transporter activity, the dopamine transporter gene (DAT1) was considered to be the prime...

The study investigated the genetic and environmental contributions to individual differences in measures of socioemotional reactivity and emotion regulation with a sample of 115 monozygotic (MZ) and 156 dizygotic (DZ) 5-month-old twin pairs. Twins' zygosity was determined by a combination of DNA typing and physical similarity. Twins' behaviors (mot...

Dysregulation of daytime cortisol activity has been associated with stress-related pathologies. Research suggests that early environmental adversity might shape cortisol activity. However, little is known about the genetic and environmental contributions to early cortisol and how this varies as a function of environmental circumstances. The goals o...

Previous studies have suggested that language is affected in infants of diabetic mothers, yet there have been no systematic investigations to address this question. Our goal was to compare infants of diabetic mothers and controls on language outcomes from ages 18 months to 7 years. This was a case-control longitudinal design with 2 birth cohorts: 1...

The negative association between attention-deficit/hyperactivity disorder (ADHD) and academic achievement is well documented (Frazier et al. J Learn Disabil 40:49–65, 2007). In a recent study, Saudino and Plomin (Child Dev 78:972–986, 2007) investigated the genetic and environmental mechanisms responsible for this association. They showed that gene...

This study investigated the understanding of false belief and emotion in monozygotic (MZ) and same-sex dizygotic (DZ) twin pairs compared to non-twin children. Aged 3;9 to 5;1 years, the children (N=123) were administered three false belief and three emotion understanding tasks. Age, family socioeconomic status, mother's level of education and lang...

The objectives of this study were to establish the different developmental trajectories of hyperactive-impulsive behaviors on the basis of both mother and father ratings at 19, 32, 50, and 63 months, and to examine the predictive validity of these trajectories with respect to later hyperactive-impulsive behaviors, as rated by teachers in the first...

Cortisol reactivity is a marker of vulnerability for a variety of stress-related diseases that likely arise from the contributions of both genetic and environmental sources of influence. However, little is known about gene-environment interplay in early cortisol reactivity. To examine the genetic and environmental contributions to early cortisol re...

Based on a sample of 406 seven-year-old twins, this study examined whether exposure to friends' social or physical aggression, respectively, moderates the effect of heritability on children's own social and physical aggression. Univariate analyses showed that children's own social and physical aggression were significantly explained by genetic fact...

Although peer victimization places children at serious risk for aggressive behavior, not all victimized children are aggressive. The diathesis-stress hypothesis of disease proposes that an environmental stressor such as peer victimization should to lead to maladjustment mostly in those individuals with preexisting genetic vulnerabilities. According...

ADHD is a heritable condition of childhood for which several risk alleles have been identified. However, observed effect sizes have been small and few replicated polymorphisms have been identified. There are many reasons for the lack of one-to-one correspondence between genotype and phenotype in ADHD. Endophenotypes are non-clinical markers of gene...

Using a genetic design of 840 60-month-old twins, this study investigated the genetic and environmental contributions to (a) individual differences in four components of cognitive school readiness, (b) the general ability underlying these four components, and (c) the predictive association between school readiness and school achievement. Results re...

Children's negative characteristics are thought to be a factor in evoking hostile parenting responses. This can result in genotype/environment correlations (rGE) in which children's heritable traits influence the parenting they experience. We did genetic analyses on 292 mothers' self-reported hostile-reactive behaviors toward each of their twins at...

To examine whether kindergarten children's genetic liability to physically aggress moderates the contribution of friends' aggression to their aggressive behaviors. Teacher and peer reports of aggression were available for 359 6-year-old twin pairs (145 MZ, 212 DZ) as well as teacher and peer reports of aggression of the two best friends of each twi...

This study examined (a) the predictive link between peer victimization and children's reactive and proactive aggression, and (b) the potential moderating effect of reciprocal friends' reactive and proactive aggression in this context. The study also examined whether these potential moderating effects of friends' characteristics were stronger with r...

Genetic and environmental contributions to body size from birth to 5 years in a population-based twin cohort were studied. Sex differences in gene-environment etiology were also explored. Analyses used data from the Quebec Newborn Twin Study (QNTS), a population-based birth cohort of 672 twin pairs. The final sample consisted of 177 complete twin p...

Functional neuroimaging studies show substantial individual variation in brain activation accompanying the experience of emotion, including sadness. Here we used functional magnetic resonance imaging (fMRI) in 104 pairs of 8-year-old twins (47 MZ, 57 DZ) to assess genetic-environmental contributions to individual differences in neural activation in...

Dominance has been conceived for a long time in terms of asymmetry in agonistic conflicts. But this conception has shown its limits in the complexity of children's social worlds. Today, dominance is rather conceived in terms of asymmetry in resource control within children's dyads. Some observational studies have been done in this context, but only...

Research in developmental psychopathology has long been preoccupied with rather broad categories of behavior, but we know little about the specific behaviors that comprise these categories. The objective of this study was to: (a) estimate the prevalence of problem and social competence behaviors in the general population of children at 17 months of...

There has been much controversy over the past decades on the origins of gender differences in children's aggressive behavior. A widely held view is that gender differences emerge sometime after 2 years of age and increase in magnitude thereafter because of gender-differentiated socialization practices. The objective of this study was to test for (a...

This study compared the contribution of genes and environment to teacher-rated reactive and proactive aggression in 6-year-old twin pairs (172 pairs: 55 monozygotic girls, 48 monozygotic boys, 33 dizygotic girls, 36 dizygotic boys). Genetic effects accounted for 39% of the variance of reactive aggression and for 41% of the variance of proactive agg...

Based on the notion that friendship may serve an important protective function against peer victimization, this study examined the moderating effect of reciprocal friends' prosociality on the link between a child's reactive aggression and victimization. The study also investigated whether a similar moderating effect could be found with respect to s...

The Longitudinal Study of Child Development in Quebec (LSCDQ) is a community study of children that examines the risk factors, such as parental depression, linked to childhood psychopathology and maladaptive functioning. Our goal was to test the construct validity of an instrument to assess major depression in the parents. Parents of a representati...

Using a genetic design of 234 six-year-old twins, this study examined (a) the contribution of genes and environment to social versus physical aggression, and (b) whether the correlation between social and physical aggression can be explained by similar genetic or environmental factors or by a directional link between the phenotypes. For social aggr...

Given the importance of parenting for the child's early socio-emotional development, parenting perceptions and behaviours, and their correlates, should be assessed as early as possible in the child's life. The goals of the present study were 1) to confirm, in two parallel population-based samples, including a large sample of twins, the factor struc...

Objectives: Physical aggression in children is a major public health problem. Not only is childhood physical aggression a precursor of the physical and mental health problems that will be visited on victims, but also aggressive children themselves are at higher risk of alcohol and drug abuse, accidents, violent crimes, depression, suicide attempts...

We compared the results of different methods for diagnosing zygosity in a sample of 237 same-sex pairs of twins assessed at 5 and 18 months of age. Despite the twins' very young age and early stage of development, physical similarity was concordant with genotyping in 91.9% of cases at 5 months and 93.8% of cases at 18 months, for a subsample of 123...

The familiality of infant sleeping heart rate (HR) and cardiac-related autonomic activity, as indexed by spectral analysis of HR variability (HRV) and response to postural change, was investigated in 322 5-month-old twin pairs. The postural change elicited only minor changes in cardiovascular activity. As a result, analyses focused on supine cardio...

In the prevention of physical aggression, possible etiological links with language development are rarely taken into account. Indeed, little is known about when language and aggressive behavior become linked during development and which mechanisms are responsible for this association. This study investigated the association between physical aggress...

In the prevention of physical aggression, possible etiological links with language development are rarely taken into account. Indeed, little is known about when language and aggressive behavior become linked during development and which mechanisms are responsible for this association. This study investigated the association between physical aggress...

A full understanding of the biology and behavior of humans cannot be complete without the collective contributions of the social sciences, cognitive sciences, and neurosciences. This book collects eighty-two of the foundational articles in the emerging discipline of social neuroscience. The book addresses five main areas of research: multilevel int...

Research is equivocal concerning the relationship between parental psychological distress and infant cognitive functioning. Four potential limitations of the literature are addressed: reliance on mothers' but not fathers' psychological distress, use of categorical measures of psychological distress, use of standardized measures of infant cognitive...

Background Studies of aggression often confound physical aggression with verbal aggression, indirect aggression, relational aggression, opposition, competition and other externalizing behaviours. Developmental models of aggression have suggested that onset of physical aggression occurs after the onset of hyperactive, stubborn and oppositional behav...

“On June 1, 1889, Charles Édouard Brown-Séquard, a prominent French physiologist, announced at the Société de Biologie in Paris that he had devised a rejuvenating therapy for the body and mind. The 72-year-old professor reported that he had drastically reversed his own decline by injecting himself with a liquid extract derived from the testicles of...

Most research on mate choice in modern societies is based on data that may or may not reflect actual mating behavior (e.g., stated preferences, personal advertisements). In the present study, real-life matings were reported by a large representative sample of men and women (N = 1,133). These data were used to test an evolutionary model in which mat...

A large sample of adult twins (1117 pairs), who were concordant for having had children were asked to report on their child-rearing practices. A 14-item version of the Parental Bonding Instrument (PBI) was used to assess rearing practices of parent twins. The two factors of Care and Overprotection, commonly found in other studies, were recovered fr...

It is shown how information on the direction of causation between variables may be obtained from a cross-sectional study of pairs of relatives. This method is applied to the study of the relationship between ratings of parents' rearing style and depression in their offspring. Adult female twins ascertained from a population-based registry in Virgin...

In most social species, position in the male social hierarchy and reproductive success are positively correlated; in humans, however, this relationship is less clear, with studies of traditional societies yielding mixed results. In the most economically advanced human populations, the adaptiveness of status vanishes altogether; social status and fe...

A socio-biological hypothesis is presented that predicts a positive relation between social and reproductive success among individuals. "A detailed theoretical model of the relation is formulated, and tested by means of a review of the pertinent studies done in modern societies, where the positive relation between the two forms of success seems the...

Résumé RÉSUMÉ/ ABSTRACT Anthropologie et Sociobiologie : Les fondements d'une possible intégration Dans cet article, nous comparons les épistémologies respectives de la sociobiologie et de l'anthropologie afin de situer leurs points d'articulation et d'établir les fondements de leur éventuelle intégration. Ces deux perspectives nous paraissent se r...

Résumé Succès social et succès reproductif dans les sociétés modernes : une analyse sociobiologique Dans cet article, nous présentons l'hypothèse sociobiologique voulant qu'il existe une relation positive entre le succès social et le succès reproductif chez les individus. Cette question se révèle particulièrement significative en ce qu'elle récapit...