Discrepancies in Perceptions of Close Relationships of Young Adolescents: A Risk for Psychopathology?

Discrepancies between children and partners (e.g., parents, friends, peers) in reports of social functioning and self-other relationships are common in clinical practice and in research. However, it is not clear whether children's biased perceptions of self-other relationships, relative to the reports of partners, are predominantly a reflection of underlying psychological dysfunctions or whether these biased perceptions present a risk factor for subsequent problematic development. This longitudinal study therefore examined the effects of adolescent-mother disagreement and adolescent-best friend disagreement in perceptions of close (dyadic) relationships on the development of psychopathology in early adolescence. The sample included 497 thirteen year-old adolescents of Dutch-Caucasian backgrounds (57 % boys; 41 % at high risk for externalizing problems), their mothers, and self-nominated best friends. The participants completed reports of positive dyadic relationship quality (warmth) in Grade 7. Discrepancy scores were based on difference scores between the adolescents' versus the partners' reports. Both absolute disagreement and direction of disagreement (i.e., over- or underestimation relative to the relationship partner) were examined. Self-reported symptoms of depression and mother-reported aggression were assessed in Grade 7, 8, and 9. Absolute disagreement in perceptions of warmth between adolescents and best friends was significantly related to higher baseline levels of aggression. No significant effects of discrepancy scores on growth curves of symptoms of depression and aggression were found. The results may suggest that it is more important for adolescents to develop positive perceptions of close relationships than to agree with partners on the quality of the relationship.status: publishe

Linking Identity and Depressive Symptoms Across Adolescence: A Multisample Longitudinal Study Testing Within-Person Effects

This multisample longitudinal study examined the directionality of effects between identity exploration and commitment processes and depressive symptoms across adolescence. We compared two theoretical perspectives. According to the vulnerability model, identity uncertainty predicts depressive symptoms, whereas the scar model holds that depressive symptoms play into identity uncertainty. In investigating both models, we examined reciprocal within-person associations in Study 1 (N = 497, Mage Time 1 [T1] = 14.03 years, comprising five annual waves) and Study 2 (N = 1,022, Mage T1 = 15.80 years, comprising four annual waves). To this end, we applied the random-intercept cross-lagged panel model (RI-CLPM) in both studies. Results supported the vulnerability model across Studies 1 and 2. Specifically, within-person increasing reconsideration of commitment (Study 1) and ruminative exploration (Study 2) predicted a within-person increase in depressive symptoms 1 year later, but not vice versa. Commitment processes did not predict depressive symptoms at the within-person level. Our findings indicate that maladaptive exploration processes of identity formation play a particularly important role in the development of depressive symptoms at the within-person level. (PsycINFO Database Record (c) 2019 APA, all rights reserved).status: publishe

GWAS of lifetime cannabis use reveals new risk loci, genetic overlap with psychiatric traits, and a causal influence of schizophrenia.

Cannabis use is a heritable trait that has been associated with adverse mental health outcomes. In the largest genome-wide association study (GWAS) for lifetime cannabis use to date (N = 184,765), we identified eight genome-wide significant independent single nucleotide polymorphisms in six regions. All measured genetic variants combined explained 11% of the variance. Gene-based tests revealed 35 significant genes in 16 regions, and S-PrediXcan analyses showed that 21 genes had different expression levels for cannabis users versus nonusers. The strongest finding across the different analyses was CADM2, which has been associated with substance use and risk-taking. Significant genetic correlations were found with 14 of 25 tested substance use and mental health-related traits, including smoking, alcohol use, schizophrenia and risk-taking. Mendelian randomization analysis showed evidence for a causal positive influence of schizophrenia risk on cannabis use. Overall, our study provides new insights into the etiology of cannabis use and its relation with mental health

Author Correction: GWAS of lifetime cannabis use reveals new risk loci, genetic overlap with psychiatric traits, and a causal effect of schizophrenia liability (Nature Neuroscience, (2018), 21, 9, (1161-1170), 10.1038/s41593-018-0206-1)

Several occurrences of the word ‘schizophrenia’ have been re-worded as ‘liability to schizophrenia’ or ‘schizophrenia risk’, including in the title, which should have been “GWAS of lifetime cannabis use reveals new risk loci, genetic overlap with psychiatric traits, and a causal effect of schizophrenia liability,” as well as in Supplementary Figures 1–10 and Supplementary Tables 7–10, to more accurately reflect the findings of the work

Author Correction: GWAS of lifetime cannabis use reveals new risk loci, genetic overlap with psychiatric traits, and a causal effect of schizophrenia liability.

Several occurrences of the word 'schizophrenia' have been re-worded as 'liability to schizophrenia' or 'schizophrenia risk', including in the title, which should have been "GWAS of lifetime cannabis use reveals new risk loci, genetic overlap with psychiatric traits, and a causal effect of schizophrenia liability," as well as in Supplementary Figures 1-10 and Supplementary Tables 7-10, to more accurately reflect the findings of the work

Genome‐wide association meta‐analysis of age at first cannabis use

Background and aimsCannabis is one of the most commonly used substances among adolescents and young adults. Earlier age at cannabis initiation is linked to adverse life outcomes, including multi-substance use and dependence. This study estimated the heritability of age at first cannabis use and identified associations with genetic variants.MethodsA twin-based heritability analysis using 8055 twins from three cohorts was performed. We then carried out a genome-wide association meta-analysis of age at first cannabis use in a discovery sample of 24 953 individuals from nine European, North American and Australian cohorts, and a replication sample of 3735 individuals.ResultsThe twin-based heritability for age at first cannabis use was 38% [95% confidence interval (CI) = 19-60%]. Shared and unique environmental factors explained 39% (95% CI = 20-56%) and 22% (95% CI = 16-29%). The genome-wide association meta-analysis identified five single nucleotide polymorphisms (SNPs) on chromosome 16 within the calcium-transporting ATPase gene (ATP2C2) at P < 5E-08. All five SNPs are in high linkage disequilibrium (LD) (r2  > 0.8), with the strongest association at the intronic variant rs1574587 (P = 4.09E-09). Gene-based tests of association identified the ATP2C2 gene on 16q24.1 (P = 1.33e-06). Although the five SNPs and ATP2C2 did not replicate, ATP2C2 has been associated with cocaine dependence in a previous study. ATP2B2, which is a member of the same calcium signalling pathway, has been associated previously with opioid dependence. SNP-based heritability for age at first cannabis use was non-significant.ConclusionAge at cannabis initiation appears to be moderately heritable in western countries, and individual differences in onset can be explained by separate but correlated genetic liabilities. The significant association between age of initiation and ATP2C2 is consistent with the role of calcium signalling mechanisms in substance use disorders