Genetic and environmental influences on developmental trajectories of adolescent alcohol use

Adolescent alcohol use demonstrates distinct developmental trajectories with different times of onset, levels, and rates of growth. Twin research on adolescent alcohol use has shown that genetic influences are consistent with a gradual growth of risks, whereas non-shared environmental influences are more consistent with an accumulation of risks over time. The current study investigated the relative contributions of genetic and environmental influences on shaping different developmental trajectories of alcohol use through adolescence. Self-reported past year alcohol use was collected from 877 Canadian twins (47.1% males) at age 13, 14, 15, and 17-year-old. Growth mixture models were fit to examine different developmental trajectories of alcohol use, and biometric liability threshold models were fit to investigate genetic and environmental influences on the liability of belonging to identified trajectories. Three trajectories were identified: low (15.1%), early onset (8.2%), and normative increasing (76.7%). Memberships in the low and early onset group were under genetic (27.6% and 34.7%), shared (42.4% and 21.5%), and non-shared environment influences (30.0% and 43.8%). Membership in the normative increasing group was under genetic (37.7%) and non-shared environment influences (62.3%). Non-shared environmental influences were significantly larger for the normative increasing trajectory than for the low trajectory. These findings provide a more refined picture of genetic and environmental influences in the development of alcohol use in subgroups of adolescents. Genetic and environmental influences both matter, but to different degrees in different trajectories. Future research should identify specific shared and non-shared environmental experiences that distinguish different trajectories

Expérimentation d’un modèle d’évaluation certificative dans un contexte d’enseignement scientifique

Le programme québécois de science et technologie est basé sur une approche par compétences. Ce choix implique des défis importants et principalement quand l’évaluation est de nature certificative. Une des compétences à évaluer concerne l’investigation scienti‐ fique. En s’appuyant sur les travaux de Rey et al. (2003), nous avons conçu un modèle d’évaluation qui permet de juger du développement de cette compétence. Différentes situa‐ tions d’évaluation ont été créés et administrées auprès de 560 élèves du secondaire pour vérifier si le modèle : (1) est adéquat pour mesurer le niveau de compétence des élèves et (2) se comporte de la même façon selon le contexte disciplinaire. Les résultats montrent que le modèle permet de classer les élèves selon trois niveaux de maîtrise : compétence assurée, compétence partielle et maîtrise des habiletés. Mots clés : évaluation, compétences, investigation scientifique The Science and Technology curriculum in the Province of Quebec, based on competencies, represents a challenge for science teachers, particularly for high‐stakes assessment. Teach‐ ers who do know how to conduct hands‐on assessment must deal with practical con‐ straints. In this context, we adapted Rey’s et al. (2003) work to construct an assessment model in relation with the Scientific Inquiry Competence. We designed different assess‐ ment situations which we administered to 560 junior high school students to verify whether a) the model is helpful in assessing learners’ level of competency in scientific in‐ quiry b) the results are comparable among disciplines on which the assessment situations are based. The results show that the model works as predicted for different learners’ levels: Full competency, Partial Competency, Skill. Key words: assessment, competencies, scientific inquiry

The dark side of friends : a genetically informed study of victimization within early adolescents’ friendships

Using a genetically informed twin design, this study examined (a) whether, in line with gene–environment correlation (rGE), a genetic disposition for anxiety puts children at risk of being victimized by a close friend or by other peers, and (b) whether, in line with gene–environment interaction (GxE), victimization by a close friend or by other peers moderates the expression of a genetic disposition for anxiety. Participants were 268 monozygotic and dizygotic twin pairs (MZ males = 71, MZ females = 80, DZ males = 56, DZ females = 61; 87% of European descent) assessed via questionnaires in Grade 8 (M age = 14.06 years, SD = 3.60). Participants reported about their victimization by a close friend and by other peers and their anxiety level. Victimization by a close friend and victimization by other peers were uncorrelated. In line with rGE, genetic factors related to anxiety predicted victimization by other peers, whereas victimization by a close friend was not predicted by heritable characteristics. Moreover, in line with a suppression process of GxE, victimization by other peers reduced the role of genetic factors in explaining interindividual differences in anxiety. In contrast, in line with a diathesis-stress process of GxE, victimization by a close friend fostered the expression of a genetic disposition for anxiety. Victimization by a close friend seems to happen to adolescents regardless of their personal, heritable characteristics. If it does occur, however, it is a source of distress mostly for youth with a genetic vulnerability for anxiety

Links between the mother-adolescent and father-adolescent relationships and adolescent depression : a genetically informed study

This study examined the unique roles of support and conflict in the relationship with the mother and the father in predicting changes in adolescents’ depressive symptoms over a 1- year period. Potential moderating effects of genetic factors (Gene × Environment interaction) and sex were also investigated. This study utilized a design of twins raised in the same family, based on a sample of 121 monozygotic and 88 dizygotic same-sex twin pairs (418 individuals; 52.2% girls) assessed in Grade 8 (M = 14.09, SD = .29) and in Grade 9 (M = 15.07, SD = .26). Depressive symptoms and the parent–adolescent relationship quality were measured with selfreport questionnaires. Multilevel regressions revealed that a lack of support in the father– adolescent relationship predicted increased depressive symptoms among all adolescents, whereas conflict in the father–adolescent relationship predicted increased depressive symptoms more strongly as adolescents’ genetic vulnerability for depressive symptoms increased. Moreover, a high level of support in the relationship with the mother predicted increased depressive symptoms in boys—but not girls—with a high genetic risk for such problems. In line with a diathesis-stress model of psychopathology, these findings suggest that relationship quality with both parents might impact girls’ and boys’ depressive symptoms but that these associations depend to some extent on adolescents’ genetic vulnerabilities

Gene-environment correlation linking aggression and peer victimization : do classroom behavioral norms matter?

Using a genetically informed design based on 197 Monozygotic and Dizygotic twin pairs assessed in grade 4, this study examined 1) whether, in line with a gene-environment correlation (rGE), a genetic disposition for physical aggression or relational aggression puts children at risk of being victimized by their classmates, and 2) whether this rGE is moderated by classroom injunctive norm salience in regard to physical or relational aggression. Physical aggression and relational aggression, as well as injunctive classroom norm salience in regard to these behaviors, were measured via peer nominations. Peer victimization was measured via self-reports. Multi-Level Mixed modeling revealed that children with a genetic disposition for either aggressive behavior are at higher risk of being victimized by their peers only when classroom norms are unfavourable toward such behaviors. However, when classroom injunctive norms favor aggressive behaviors, a genetic disposition for physical or relational aggression may actually protect children against peer victimization. These results lend further support to the notion that bullying interventions must include the larger peer context instead of a sole focus on victims and bullies

Longitudinal links between gambling participation and academic performance in youth : a test of four models

Gambling participation and low academic performance are related during adolescence, but the causal mechanisms underlying this link are unclear. It is possible that gambling participation impairs academic performance. Alternatively, the link between gambling participation and low academic performance could be explained by common underlying risk factors such as impulsivity and socio-family adversity. It could also be explained by other current correlated problem behaviors such as substance use. The goal of the present study was to examine whether concurrent and longitudinal links between gambling participation and low academic performance exist from age 14 to age 17 years, net of common antecedent factors and current substance use. A convenience sample of 766 adolescents (50.6% males) from a longitudinal twin sample participated in the study. Analyses revealed significant, albeit modest, concurrent links at both ages between gambling participation and academic performance. There was also a longitudinal link between gambling participation at age 14 and academic performance at age 17, which persisted after controlling for age 12 impulsivity and socio-family adversity as well as current substance use. Gambling participation predicts a decrease in academic performance during adolescence, net of concurrent and antecedent personal and familial risk factors

Personal and familial predictors of peer victimization trajectories from primary to secondary school

Using a sample of 767 children (403 girls, 364 boys), this study aimed to 1) identify groups with distinct trajectories of peer victimization over a six-year period from primary school through the transition to secondary school, and 2) examine the associated personal (i.e., aggression or internalizing problems) and familial (family status, SES, the parent-child relationship) predictors. Peer victimization was assessed via self-reports from grades 4 through 9 (ages 10 through 15 years), aggression and internalizing problems were assessed in grade 4 via peer nominations, and the parent-child relationship was assessed in grade 7 (i.e., right after the transition to secondary school) via parent-reports. Growth Mixture modeling revealed one group (62%) who experienced little victimization in primary school and even less in secondary school, another group (31%) who was victimized in primary but not or much less in secondary school, and a third group (7%) who was chronically victimized across in both school contexts. Boys were more likely than girls to follow any elevated victimization trajectory. Chronic victimization across primary and secondary school was predicted by non-intact family status and a combination of both internalizing problems and aggression compared to non-victimized youth. In contrast, transitory victimization during primary but not in secondary school was predicted by aggression, but not internalizing problems. Support as well as conflict in the parent-child relationship also showed significant, albeit distinct associations with the different peer victimization trajectories

The bidirectional association between maternal speech and child characteristics

Our aim was to assess whether infants influence the quantity and quality of their mothers’ speech to them and, in turn, whether this maternal speech influences children’s later language. As 189 mothers interacted with each of their twins at 0;5, we calculated the number of utterances, the proportion of sensitive utterances, and the proportion of self-repeated utterances they produced. We later assessed the twins’ language comprehension and production when they were 1;6, 2;6, and 5;2. Quantity of maternal speech predicted child language at 5;2, whereas sensitivity predicted child language at 2;6 and 5;2 and partial self-repetition predicted child language at 1;6. Conversely, sensitivity and partial self-repetition in maternal speech at 0;5 were associated with genetic factors from the child, indicating that infant characteristics influence the quality of maternal speech. Overall, our findings stress the importance of considering both directions in the association between maternal speech and child characteristics