Gene-environment interaction and psychiatric disorders: Review and future directions

Stress sensitization to psychological adjustment following childhood adversity: Moderation by serotonergic multilocus genetic variation

BACKGROUND

Exposure to adverse childhood experiences may heighten adolescents' sensitivity to stress, which influences their psychological adjustment over their lifetimes. Some research indicates that serotonergic genetic variation moderates how environmental stressors impact psychological adjustment. However, there are recognized limitations in examining gene-environment interactions using only single polymorphisms.

METHODS

The present study employed a multilocus genetic profile score (MGPS) approach to measure serotonergic genetic variations and examines their interaction with childhood abuse and friendship quality as predictors of the outcomes of psychological adjustment (depressive symptoms and sleep problems) in an adolescent sample (14.15 ± 0.63 years; N = 525).

RESULTS

Serotonergic genetic factors moderated stress sensitivity induced by adverse childhood experiences. Adolescent psychological adjustment appeared to result from interactions between genetics and the environments. These findings were further supported by rigorous significance testing and sensitivity analyses.

CONCLUSION

The results highlight the strong utility of using MGPS to investigate gene-environment-environment interactions related to adolescent psychological adjustment.

Associations of polygenic risk score, environmental factors, and their interactions with the risk of schizophrenia spectrum disorders

BACKGROUND

Emerging evidence indicates that gene-environment interactions (GEIs) are important underlying mechanisms for the development of schizophrenia (SZ). We investigated the associations of polygenic risk score for SZ (PRS-SZ), environmental measures, and their interactions with case-control status and clinical phenotypes among patients with schizophrenia spectrum disorders (SSDs).

METHODS

The PRS-SZ for 717 SSD patients and 356 healthy controls (HCs) were calculated using the LDpred model. The Korea-Polyenvironmental Risk Score-I (K-PERS-I) and Early Trauma Inventory-Self Report (ETI-SR) were utilized as environmental measures. Logistic and linear regression analyses were performed to identify the associations of PRS-SZ and two environmental measures with case-control status and clinical phenotypes.

RESULTS

The PRS-SZ explained 8.7% of SZ risk. We found greater associations of PRS-SZ and total scores of the K-PERS-I with case-control status compared to the ETI-SR total score. A significant additive interaction was found between PRS-SZ and K-PERS-I. With the subdomains of the K-PERS-I and ETI-SR, we identified significant multiplicative or additive interactions of PRS-SZ and parental socioeconomic status (pSES), childhood adversity, and recent life events in association with case-control status. For clinical phenotypes, significant interactions were observed between PRS-SZ and the ETI-SR total score for negative-self and between PRS-SZ and obstetric complications within the K-PERS-I for negative-others.

CONCLUSIONS

Our findings suggest that the use of aggregate scores for genetic and environmental measures, PRS-SZ and K-PERS-I, can more accurately predict case-control status, and specific environmental measures may be more suitable for the exploration of GEIs.

Associations between multiple ambient air pollutants, genetic risk, and incident mental disorders: An interaction study in the UK population

Mental disorders can be triggered by genetic and environmental risk factors. Limited studies have explored the effects of long-term exposure to air pollution on mental disorders, and most of the studies have focused on individual air pollutants. This study aimed to examine the relationship between long-term exposure to multiple air pollutants and incident mental disorders, including depression, anxiety, and schizophrenia, and whether the associations were affected by genetic susceptibility. Participants in the UK Biobank with no history of mental disorders were followed from baseline (2006 to 2010) to October 31st, 2022. Cox regression was applied to evaluate the correlation between PM2.5 absorbance, PM2.5, PM2.5-10, PM10, NO2, and NOx and any or specific mental disorders. Additive and multiplicative scales were used to measure the interaction between air pollution and schizophrenia polygenic risk score (PRS), depression PRS, or anxiety PRS on specific mental diseases. After a median of 13.36 years of follow-up on 252,376 participants, we observed per interquartile increase of PM2.5 absorbance (0.32 per meter), PM2.5 (1.28 μg/m3), NO2 (10.08 μg/m3), and NOx (16.78 μg/m3) were related to a 2-6 % higher risk of incident mental disorders. The HR (95 % CI) of incident mental disorder for the 2nd, 3rd, and 4th quartile of the air pollution score were 1.05 (1.01-1.18), 1.13 (1.09-1.18), and 1.14 (1.09-1.19), respectively, in comparison to the lowest level of the score. Per interquartile increase in the air pollution score was associated with a 6 %, 24 %, 4 %, and 6 % higher risk of incident mental disorders, schizophrenia, depression, and anxiety, respectively. No interaction between air pollution and genetic risk of schizophrenia, depression or anxiety on corresponding incident disorders was observed. These findings emphasize the importance of implementing air pollution control standards to decrease the burden of mental disorders.

The effects of life experiences and polygenic risk for depression on the development of positive and negative cognitive biases across adolescence: The CogBIAS hypothesis

The Cognitive Bias (CogBIAS) hypothesis proposes that cognitive biases develop as a function of environmental influences (which determine the valence of biases) and the genetic susceptibility to those influences (which determines the potency of biases). The current study employed a longitudinal, polygenic-by-environment approach to examine the CogBIAS hypothesis. To this end, measures of life experiences and polygenic scores for depression were used to assess the development of memory and interpretation biases in a three-wave sample of adolescents (12-16 years) (N = 337). Using mixed effects modeling, three patterns were revealed. First, positive life experiences (PLEs) were found to diminish negative and enhance positive forms of memory and social interpretation biases. Second, and against expectation, negative life experiences and depression polygenic scores were not associated with any cognitive outcomes, upon adjusting for psychopathology. Finally, and most importantly, the interaction between high polygenic risk and greater PLEs was associated with a stronger positive interpretation bias for social situations. These results provide the first line of polygenic evidence in support of the CogBIAS hypothesis, but also extend this hypothesis by highlighting positive genetic and nuanced environmental influences on the development of cognitive biases across adolescence.

Prenatal maternal stress: triangulating evidence for intrauterine exposure effects on birth and early childhood outcomes across multiple approaches

BACKGROUND

Maternal stress during pregnancy may impact offspring development via changes in the intrauterine environment. However, genetic and environmental factors shared between mothers and children might skew our understanding of this pathway. This study assesses whether prenatal maternal stress has causal links to offspring outcomes: birthweight, gestational age, or emotional and behavioral difficulties, triangulating across methods that account for various measured and unmeasured confounders.

METHODS

We used data from the Norwegian Mother, Father, and Child Cohort Study (MoBa), including maternal reports on prenatal stress at work, at home, and via stressful life events as exposures. Outcomes were children's birthweight and gestational age, from the Medical Birth Registry of Norway, and maternal reports on early offspring emotional and behavioral difficulties. We assessed associations using four approaches: sibling control analyses, gene-environment interaction analyses, intergenerational Mendelian randomization (MR), and negative control (i.e., postnatal stress) analyses.

RESULTS

Maternal prenatal stress was observationally associated with offspring lower birthweight (e.g., βwork = - 0.01 [95%CI: - 0.02, - 0.01]), earlier birth (e.g., βwork = - 0.04 [95%CI: - 0.04, - 0.03])), and more emotional (e.g., βevents = 0.08 [95%CI: 0.07, 0.09]) and behavioral difficulties (e.g., βrelationship = 0.08 [95%CI: 0.07, 0.09]) in the full sample (N = 112,784). However, sibling control analyses (N = 36,511) revealed substantial attenuation of all associations after accounting for familial factors. Gene-environment interaction models (N = 76,288) showed no clear evidence of moderation of associations by mothers' polygenic scores for traits linked to stress sensitivity. Intergenerational MR analyses (N = 29,288) showed no clear evidence of causal effects of maternal plasma cortisol on any offspring outcomes. Negative control exposure analyses revealed similar effect sizes whether exposures were measured prenatally or postnatally.

CONCLUSIONS

Our results indicate that links between prenatal maternal stress and variation in early offspring outcomes are more likely to be confounded than causal. While no observational study can rule out causality, the consistency of our findings across different approaches is striking. Other sources of prenatal stress or more extreme levels may represent intrauterine causal risk factors for offspring development. Nonetheless, our research contributes to identifying boundary conditions of the fetal programming and developmental origins of health and disease hypotheses, which may not be as universal as sometimes assumed.

Shedding Light on Antisocial Behavior Through Genetically Informed Research

Antisocial behavior (ASB) refers to a set of behaviors that violate social norms and disregard the well-being and rights of others. In this review, we synthesize evidence from studies using genetically informed designs to investigate the genetic and environmental contributions to individual differences in ASB. We review evidence from studies using family data (twin and adoption studies) and measured DNA (candidate gene and genome-wide association studies) that have informed our understanding of ASB. We describe how genetically informative designs are especially suited to investigate the nature of environmental risk and the forms of gene-environment interplay. We also highlight clinical and legal implications, including how insights from genetically informed research can help inform prevention and intervention, and we discuss some challenges and opportunities within this field of research.

Positive association between Internet use and mental health among adults aged ≥50 years in 23 countries

The Internet is increasingly important in addressing age-related mental health challenges. We used linear mixed models and meta-analyses to examine the association between Internet use and mental health among 87,559 adults aged ≥50 years from 23 countries. Internet use was associated with fewer depressive symptoms (pooled average marginal effect (AME), -0.09; 95% confidence interval (CI), -0.12 to -0.07), higher life satisfaction (pooled AME, 0.07; 95% CI, 0.05 to 0.10) and better self-reported health (pooled AME, 0.15; 95% CI, 0.12 to 0.17). For two countries (the USA and England) with genetic data available, positive associations between Internet use and mental health were observed across three genetic risk categories. For three countries (the USA, England and China), a higher frequency of Internet use was related to better mental health. Our findings are relevant to public health policies and practices in promoting mental health in later life through the Internet, especially in countries with limited Internet access and mental health services.

Polygenic risk for epigenetic aging and adverse life experiences interact to predict growth in adolescent depression in a racially/ethnically diverse sample

Introduction

Research has yet to examine the interplay between indices of environmental risk and resilience processes and genetic predisposition for epigenetic aging in predicting early adolescent depressive symptoms. In the current study we examine whether adverse life events and parental acceptance moderate polygenic predisposition for GrimAge epigenetic aging in predicting trajectories of depressive symptoms across early adolescence.

Method

Using data from the Adolescent Brain Development Study (ABCD, N = 11,875), we created polygenic scores for GrimAge, and examined whether exposure to adverse life events and parental acceptance moderated the relation between genetic risk and depressive symptom trajectories from age 10/11 to 12/13 using growth mixture modelling. We examined models separately in European American (EA), African American (AA), and Latinx (LX) subgroups of ABCD.

Results

In the EA and AA subgroups, adverse life events moderated polygenic scores for GrimAge such that there was increased likelihood of membership in a higher vs. lower depression trajectory.

Discussion

We extend literature by identifying genetic contributions to epigenetic aging as a depression diathesis in adolescence. Findings also highlight the detrimental role of adverse life events in exacerbating genetic risk for the development of depression in adolescence.

Research Review: A review of the past decade of family and genomic studies on adolescent mental health

BACKGROUND

Mental health problems and traits capturing psychopathology are common and often begin during adolescence. Decades of twin studies indicate that genetic factors explain around 50% of individual differences in adolescent psychopathology. In recent years, significant advances, particularly in genomics, have moved this work towards more translational findings.

METHODS

This review provides an overview of the past decade of genetically sensitive studies on adolescent development, covering both family and genomic studies in adolescents aged 10-24 years. We focus on five research themes: (1) co-occurrence or comorbidity between psychopathologies, (2) stability and change over time, (3) intergenerational transmission, (4) gene-environment interplay, and (5) psychological treatment outcomes.

RESULTS

First, research shows that much of the co-occurrence of psychopathologies in adolescence is explained by genetic factors, with widespread pleiotropic influences on many traits. Second, stability in psychopathology across adolescence is largely explained by persistent genetic influences, whereas change is explained by emerging genetic and environmental influences. Third, contemporary twin-family studies suggest that different co-occurring genetic and environmental mechanisms may account for the intergenerational transmission of psychopathology, with some differences across psychopathologies. Fourth, genetic influences on adolescent psychopathology are correlated with a wide range of environmental exposures. However, the extent to which genetic factors interact with the environment remains unclear, as findings from both twin and genomic studies are inconsistent. Finally, a few studies suggest that genetic factors may play a role in psychological treatment response, but these findings have not yet been replicated.

CONCLUSIONS

Genetically sensitive research on adolescent psychopathology has progressed significantly in the past decade, with family and twin findings starting to be replicated at the genomic level. However, important gaps remain in the literature, and we conclude by providing suggestions of research questions that still need to be addressed.

Genetic vulnerability and adverse mental health outcomes following mild traumatic brain injury: a meta-analysis of CENTER-TBI and TRACK-TBI cohorts

Background

Post-traumatic stress disorder (PTSD) and depression are common after mild traumatic brain injury (mTBI), but their biological drivers are uncertain. We therefore explored whether polygenic risk scores (PRS) derived for PTSD and major depressive disorder (MDD) are associated with the development of cognate TBI-related phenotypes.

Methods

Meta-analyses were conducted using data from two multicenter, prospective observational cohort studies of patients with mTBI: the CENTER-TBI study (ClinicalTrials.gov ID NCT02210221) in Europe (December 2014-December 2017) and the TRACK-TBI study in the US (March 2014-July 2018). In both cohorts, the most common causes of injury were road traffic accidents and falls. Primary outcomes, specifically probable PTSD and depression, were defined at 6 months post-injury using scores ≥33 on the PTSD Checklist-5 and ≥15 on the Patient Health Questionnaire-9, respectively. We calculated PTSD-PRS and MDD-PRS for patients aged ≥17 years who had a Glasgow Coma Scale score of 13-15 upon hospital arrival and assessed their association with PTSD and depression following TBI. We also evaluated the transferability of the findings in a cohort of African Americans.

Findings

Overall, 11.8% (219/1869) and 6.7% (124/1869) patients were classified as having probable PTSD and depression, respectively. The PTSD-PRS was significantly associated with higher adjusted odds of PTSD in both cohorts, with a pooled odds ratio (OR) of 1.55 [95% confidence interval (CI) 1.30-1.84, p < 0.001, I 2  = 20.8%]. Although the MDD-PRS increased the risk of depression after TBI, it did not reach significance in the individual cohorts. However, in a combined analysis, the risk was significantly elevated with a pooled OR of 1.26 [95% CI 1.03-1.53, p = 0.02, I 2  = 0%]. The addition of PRSs improved the proportion of outcome variance explained in the two study cohorts from 19.5% and 30.3% to 21.6% and 34.0% for PTSD; and from 11.0% and 22.5% to 12.8% and 22.6% for depression. Patients in the highest cognate PRS quintile had increased odds of 3.16 [95% CI 1.80-5.55] and 2.03 [95% CI 1.04-3.94] of developing PTSD or depression compared to the lowest quintile, respectively.

Interpretation

Associations of PRSs with PTSD and depression following TBI are not disorder-specific. However, the overlap between MDD-PRS and depression following TBI is less robust compared to PTSD-PRS and PTSD. PRSs could improve risk prediction, and permit enrichment for interventional trials.

Funding

This study was supported by funding by an FP7 grant from the European Union, Hannelore Kohl Stiftung, Integra LifeSciences Corporation, NeuroTrauma Sciences, US National Institutes of Health, US Department of Defense, National Football League Advisory Board, US Department of Energy, and One Mind.

BMAL1-Potential Player of Aberrant Stress Response in Q31L Mice Model of Affective Disorders: Pilot Results

Dysregulation in the stress-response system as a result of genetical mutation can provoke the manifestation of affective disorders under stress conditions. Mutations in the human DISC1 gene is one of the main risk factors of affective disorders. It was known that DISC1 regulates a large number of proteins including BMAL1, which is involved in the regulation of glucocorticoid synthesis in the adrenal glands and the sensitivity of glucocorticoid receptor target genes. Male mice with a point mutation Q31L in the Disc1 gene were exposed to chronic unpredictable stress (CUS), after which the behavioral and physiological stress response assessed. To assess whether there were any changes in BMAL1 in key brain regions involved in the stress response, immunohistochemistry was applied. It was shown that the Q31L mice had an aberrant behavioral response, especially to the 2 weeks of CUS, which was expressed in unchanged motor activity, increased time of social interaction, and alterations in anxiety and fear-related behavior. Q31L males did not show an increase in blood corticosterone levels after CUS and a decrease in body weight. Immunohistochemical analysis in intact Q31L mice revealed a decrease in BMAL1 immunofluorescence in the CA1 hippocampal area and lateral habenula. Thus, the Q31L mutation of the Disc1 gene disrupts behavioral and physiological stress response and the BMAL1 dysregulation may underlie it, so this protein can act as a molecular target for the treatment of affective disorders.

Onset age moderates the associations between neutrophil-to-lymphocyte ratio and clinical symptoms in first-episode patients with schizophrenia

Patients with schizophrenia with early onset age have been shown to exhibit more severe negative symptoms. Genetic, biomarker, postmortem brain, and imaging studies indicate the involvement of immune abnormalities in the pathophysiology of schizophrenia. In this study, we examined the moderating role of early onset on the associations between clinical symptoms and neutrophil-to-lymphocyte ratio (NLR) in medication-naïve first-episode schizophrenia (MNFES). A total of 97 MNFES patients were recruited. Neutrophil (NEU), LYM, and NLR values were compared between early-onset (EO) and non-early-onset (non-EO) patients with schizophrenia to explore the potential influence of EO on the correlations between NLR and symptoms. The results showed no differences in NEU and NLR values between the EO and non-EO groups. In the EO group, NEU and NLR values significantly correlated with general psychopathology and total score (all p < 0.05), whereas lymphocyte counts were not correlated with symptoms of schizophrenia. NEU and NLR were not associated with symptoms in the non-EO group. Linear regression analysis in the EO group revealed that NEU or NLR values were a predictive biomarker for the clinical symptoms. Our study indicates that EO patients had greater severe negative symptoms compared with non-EO patients. In addition, onset age mediates the relationships of NEU and NLR values with clinical symptoms, suggesting that an immune disturbance, particularly increased innate immune response in EO patients, may be involved in the psychophysiology of schizophrenia.

The impact of genetic variations in the serotonergic system on symptom severity and clinical outcome in functional neurological disorders

OBJECTIVE

We studied gene-environment, as well as gene-gene interaction to elucidate their effects on symptom severity and predict clinical outcomes in functional neurological disorders (FND).

METHODS

Eighty-five patients with mixed FND were genotyped for ten single-nucleotide polymorphisms (SNP) from seven different stress-related genes. We tested cross-sectionally the association between genotype and the symptomatology of FND (symptom severity assessed with the examiner-based clinical global impression score [CGI] and age of onset). Clinical outcome was assessed in 52 patients who participated in a follow-up clinical visit after eight months (following their individual therapies as usual). We tested longitudinally the association between genotype and clinical outcome in FND. We examined the contribution of each SNP and their interaction between them to FND symptomatology and outcome.

RESULTS

We identified a nominal association between tryptophan hydroxylase 1 (TPH1) rs1800532 and symptom severity (CGI1) in FND under a codominant model (T/T: ßT/T = 2.31, seT/T = 0.57; G/T: ßG/T = -0.18, seG/T = 0.29, P = 0.035), with minor allele (T) carriers presenting more severe symptoms. An association was identified between TPH1 and clinical outcome, suggesting that major allele (G) carriers were more likely to have an improved outcome under a codominant model (G/T: ORG/T = 0.18, CIG/T = [0.02-1.34]; T/T: ORT/T = 2.08, CIT/T = [0.30-14.53], P = 0.041). Our analyses suggested a significant gene-gene interaction for TPH2 (rs4570625) and OXTR (rs2254298) on symptom severity, and a significant gene-gene interaction for TPH1, TPH2 and BDNF (rs1491850) on clinical outcome.

CONCLUSION

FND might arise from a complex interplay between individual predisposing risk genes involved in the serotonergic pathway and their gene-gene interactions.

Dopaminergic Epistases in Schizophrenia

Background: The dopaminergic theory, the oldest and most comprehensively analyzed neurotransmitter theory of schizophrenia, remains a focal point of research. Methods: This systematic review examines the association between combinations of 14 dopaminergic genes and the risk of schizophrenia. The selected genes include dopamine receptors (DRD1-5), metabolizing enzymes (COMT, MAOA, MAOB, DBH), synthesizing enzymes (TH, DDC), and dopamine transporters (DAT, VMAT1, and VMAT2). Results: Recurring functional patterns show combinations with either hyperdopaminergic effects in limbic and striatal regions or high striatal and low prefrontal dopamine levels. The protective statuses of certain alleles or genotypes are often maintained in epistatic effects; however, exceptions exist. This complexity could explain the inconsistent results in previous genetic studies. Investigating individual alleles may be insufficient due to the heterozygous advantage observed in some studies. Conclusions: Schizophrenia may not be a monolithic disease, but rather a sum of different phenotypes which respond uniquely to different treatment and prevention approaches.

Building machine learning prediction models for well-being using predictors from the exposome and genome in a population cohort

Effective personalized well-being interventions require the ability to predict who will thrive or not, and the understanding of underlying mechanisms. Here, using longitudinal data of a large population cohort (the Netherlands Twin Register, collected 1991-2022), we aim to build machine learning prediction models for adult well-being from the exposome and genome, and identify the most predictive factors (N between 702 and 5874). The specific exposome was captured by parent and self-reports of psychosocial factors from childhood to adulthood, the genome was described by polygenic scores, and the general exposome was captured by linkage of participants' postal codes to objective, registry-based exposures. Not the genome (R 2 = -0.007 [-0.026-0.010]), but the general exposome (R 2 = 0.047 [0.015-0.076]) and especially the specific exposome (R 2 = 0.702 [0.637-0.753]) were predictive of well-being in an independent test set. Adding the genome (P = 0.334) and general exposome (P = 0.695) independently or jointly (P = 0.029) beyond the specific exposome did not improve prediction. Risk/protective factors such as optimism, personality, social support and neighborhood housing characteristics were most predictive. Our findings highlight the importance of longitudinal monitoring and promises of different data modalities for well-being prediction.

Association of Non-Suicidal Self-Injury with Tryptophan Hydroxylase 2 Gene Polymorphism and Negative Life Events Among Adolescents with Depression in Northern China

Objective

To investigate the association between single nucleotide polymorphisms (SNPs) of tryptophan hydroxylase 2 (TPH2) (rs11178997, rs11178998, and rs120074175) and negative life events in adolescent depression with Non-suicidal self-injury (NSSI).

Methods

Genomic DNA was extracted from 197 adolescents with depression (participants group, including NSSI group and non-NSSI group), as well as from 100 healthy controls (control group), in northern China. PCR technology was utilized to amplify DNA fragments and detect genotypes in both groups. The Adolescent Life Event Scale (ASLEC) was employed to conduct a questionnaire survey among the participants and control groups. Differences in allele and genotype frequency distribution between the two groups were analyzed using the X^2 test, while generalized multifactor dimensionality reduction (GMDR) was used to analyze gene-environment interactions.

Results

Significant differences were observed in ASLEC scores between the control group and both the NSSI group and non-NSSI group (P<0.05). Additionally, significant differences were found in the interpersonal relationship factor and punishment factor between the NSSI group and non-NSSI group (P < 0.05). Moreover, a significant difference was identified in SNP genotype of rs11178997 between the depression group (NSSI group + non-NSSI group) and control group (P<0.05). GMDR analysis revealed an interaction among rs11178997, rs11178998, and ASLEC.

Conclusion

Adolescents with depression, particularly females, may exhibit a tendency to employ NSSI as an emotional coping mechanism when confronted with greater family and interpersonal challenges. The AT genotype of TPH2 gene locus rs11178997 is more prevalent among adolescents with depression. Furthermore, the occurrence of NSSI may be associated with an interaction involving polymorphic sites rs11178997 and rs11178998 along with life events.

The impact of ATP-binding cassette transporters in the diseased brain: Context matters

ATP-binding cassette (ABC) transporters facilitate the movement of diverse molecules across cellular membranes, including those within the CNS. While most extensively studied in microvascular endothelial cells forming the blood-brain barrier (BBB), other CNS cell types also express these transporters. Importantly, disruptions in the CNS microenvironment during disease can alter transporter expression and function. Through this comprehensive review, we explore the modulation of ABC transporters in various brain pathologies and the context-dependent consequences of these changes. For instance, downregulation of ABCB1 may exacerbate amyloid beta plaque deposition in Alzheimer's disease and facilitate neurotoxic compound entry in Parkinson's disease. Upregulation may worsen neuroinflammation by aiding chemokine-mediated CD8 T cell influx into multiple sclerosis lesions. Overall, ABC transporters at the BBB hinder drug entry, presenting challenges for effective pharmacotherapy. Understanding the context-dependent changes in ABC transporter expression and function is crucial for elucidating the etiology and developing treatments for brain diseases.

Genetic propensity to depression and the role of partnership status

Social relationships and genetic propensity are known to affect depression risk, but their joint effects are poorly understood. This study examined the association of a polygenic index for depression with time to antidepressant (AD) purchasing and the moderating role of partnership status. We analysed data from 30,192 Finnish individuals who participated in the FINRISK and Health 2000 and 2011 surveys and had register and medication data available. We measured genetic risk with a polygenic index (PGI) for depression. Depression was assessed through antidepressant purchases. We estimated an accelerated failure time model with partnership status as time-varying and different sets of confounder adjustments. The predicted cumulative hazard of antidepressant purchasing varied across PGI and partnership status. At follow-up year 10, being widowed was associated with the largest cumulative hazard of 0.34 (95%CI: 0.28-0.39) in the 80th and 0.20 (95%CI: 0.17-0.23) in the 20th PGI percentile, followed by divorced, single, married and cohabiting. Cohabiting was associated with a cumulative hazard of 0.19 (95%CI: 0.16-0.23) in the 80th and 0.11 (95%CI: 0.1-0.13) in the 20th PGI percentile. We found no evidence for an interaction between the PGI and partnership status. Results were robust to different model specifications, gender stratification, and the choice of PGI. Although antidepressant purchasing correlated with both PGI and partnership status, we found no evidence that partnership status could partially offset or amplify the association between the PGI for depression and antidepressant purchasing incidence.

Assessing the impact of psychiatric genetic counseling on psychiatric hospitalizations

Psychiatric genetic counseling (pGC) can improve patient empowerment and self-efficacy. We explored the relationship between pGC and psychiatric hospitalizations, for which no prior data exist. Using Population Data BC (a provincial dataset), we tested two hypotheses: (1) among patients (>18 years) with psychiatric conditions who received pGC between May 2010 and Dec 2016 (N = 387), compared with the year pre-pGC, in the year post-pGC there would be fewer (a) individuals hospitalized and (b) total hospital admissions; and (2) using a matched cohort design, compared with controls (N = 363, matched 1:4 for sex, diagnosis, time since diagnosis, region, and age, and assigned a pseudo pGC index date), the pGC cohort (N = 91) would have (a) more individuals whose number of hospitalizations decreased and (b) fewer hospitalizations post-pGC/pseudo-index. We also explored total days in hospital. Within the pGC cohort, there were fewer hospitalizations post-pGC than pre- pGC (p = 0.011, OR = 1.69), and total days in hospital decreased (1085 to 669). However, when compared to matched controls, the post-pGC/pseudo index change in hospitalizations among pGC cases was not statistically significant, even after controlling for the higher number of hospitalizations prior. pGC may lead to fewer psychiatric hospitalizations and cost savings; further studies exploring this are warranted.

LDER-GE estimates phenotypic variance component of gene-environment interactions in human complex traits accurately with GE interaction summary statistics and full LD information

Gene-environment (GE) interactions are essential in understanding human complex traits. Identifying these interactions is necessary for deciphering the biological basis of such traits. In this study, we review state-of-art methods for estimating the proportion of phenotypic variance explained by genome-wide GE interactions and introduce a novel statistical method Linkage-Disequilibrium Eigenvalue Regression for Gene-Environment interactions (LDER-GE). LDER-GE improves the accuracy of estimating the phenotypic variance component explained by genome-wide GE interactions using large-scale biobank association summary statistics. LDER-GE leverages the complete Linkage Disequilibrium (LD) matrix, as opposed to only the diagonal squared LD matrix utilized by LDSC (Linkage Disequilibrium Score)-based methods. Our extensive simulation studies demonstrate that LDER-GE performs better than LDSC-based approaches by enhancing statistical efficiency by ~23%. This improvement is equivalent to a sample size increase of around 51%. Additionally, LDER-GE effectively controls type-I error rate and produces unbiased results. We conducted an analysis using UK Biobank data, comprising 307 259 unrelated European-Ancestry subjects and 966 766 variants, across 217 environmental covariate-phenotype (E-Y) pairs. LDER-GE identified 34 significant E-Y pairs while LDSC-based method only identified 23 significant E-Y pairs with 22 overlapped with LDER-GE. Furthermore, we employed LDER-GE to estimate the aggregated variance component attributed to multiple GE interactions, leading to an increase in the explained phenotypic variance with GE interactions compared to considering main genetic effects only. Our results suggest the importance of impacts of GE interactions on human complex traits.

Decomposing the variance in early maladaptive schemas: the major role of one general factor, the minor role of domains, and their differential relations to facial emotion recognition

Introduction

Despite the growing interest in the early maladaptive schemas, the progress in understanding their impacts is decelerated by a lack of clear understanding of their structure. Different composite scores are calculated without a solid ground or a clarified meaning. Here we explain that the schema variance can be theoretically decomposed into three components: schema-specific, domain-specific due to the unmet core needs, and the common variance we call general susceptibility; each can differentially correlate with other substantive variables. Using this framework, we empirically examine the structure of schemas and their relationships to facial emotion recognition, a crucial ability that can widely affect our social interactions.

Methods

A sample of adults completed an emotion recognition task and the Young Schema Questionnaire. Using different factor models, the specific and shared variance across schemas was analyzed. Then, the relation of these variance components to facial emotion recognition was explored.

Results

A general factor explained 27%, 40%, and 64% of the total variance in items, schemas, and domains, respectively. Partialling out the common variance, there was little domain-specific variance remained. Regarding facial emotion recognition, they were not correlated with specific schemas; however, the general susceptibility factor was correlated with anger recognition.

Discussion

The variance decomposition approach to schemas, which uses the bifactor model, may offer a clearer way to explore the impacts of schemas. While domain scores are widely used, their reliability, validity, and meaning are questionable. The generic factor, which is consistently extractable from empirical data, requires further attention.

Cumulative Genetic Scores Interact with Maternal and Paternal Parenting in Predicting Parent-Adolescent Cohesion and Conflict

Previous research concerning the interplay between genetics and parenting in the development of the parent-child relationship during adolescence has been extremely scarce, predominantly adopting single-gene designs. This limited body of work has largely overlooked the distinct effects of maternal and paternal roles, as well as potential gender differences. Additionally, existing gene-by-environment (G × E) studies have mainly concentrated on adverse environmental factors and associated negative outcomes, somewhat neglecting positive environments and outcomes. The present study examined the interactions of cumulative genetic scores (CGS, dopamine receptor D2 TaqIA and oxytocin receptor gene rs53576 polymorphisms) with both positive and negative parenting on parent-adolescent cohesion and conflict. Furthermore, this study aimed to ascertain with which gene-environment model the potential G × E interactions would align. A total of 745 Chinese Han adolescents (Mage = 13.36 ± 0.96 years; 46.8% girls) from grades 7 to 9 participated in this study. Results revealed a significant effect of CGS and negative maternal parenting on mother-adolescent conflict among males, consistent with the weak differential susceptibility model. As CGS increased, the effects of negative maternal parenting on mother-son conflict were magnified. These findings have implications for the timing and focus of interventions aimed at improving parent-adolescent relationships.

Cardiomyopathies and Psychiatric Disorders: An Overview and General Clinical Recommendations

The association between cardiomyopathies (CMPs) and psychiatric disorders is a complex and bidirectional phenomenon that involves multiple mechanisms and factors. CMPs may raise the risk of psychiatric disorders due to the psychological stress, physical limitations, social isolation, or poor prognosis associated with the underlying disease. Psychiatric disorders, on the other hand, can increase the possibility of developing or worsening CMPs due to the behavioral, neuroendocrine, inflammatory, or pharmacological effects of mental illness or its treatment. Moreover, some common genetic or environmental factors may have a relevant influence on both conditions. With this comprehensive review, we sought to provide an overview of the current evidence on the strict and intriguing interconnection between CMPs and psychiatric disorders, focusing on the epidemiology, pathophysiology, clinical implications, and management strategies.

An Interpretable Machine Learning Approach to Predict Sensory Processing Sensitivity Trait in Nursing Students

Sensory processing sensitivity (SPS) is a personality trait that makes certain individuals excessively sensitive to stimuli. People carrying this trait are defined as Highly Sensitive People (HSP). The SPS trait is notably prevalent among nursing students and nurse staff. Although there are HSP diagnostic tools, there is little information about early detection. Therefore, the aim of this work was to develop a prediction model to identify HSP and provide an individualized nursing assessment. A total of 672 nursing students completed all the evaluations. In addition to the HSP diagnosis, emotional intelligence, communication skills, and conflict styles were evaluated. An interpretable machine learning model was trained to predict the SPS trait. We observed a 33% prevalence of HSP, which was higher in women and people with previous health training. HSP were characterized by greater emotional repair (p = 0.033), empathy (p = 0.030), respect (p = 0.038), and global communication skills (p = 0.036). Overall, sex and emotional intelligence dimensions are important to detect this trait, although personal characteristics should be considered. The present individualized prediction model could help to predict the presence of the SPS trait in nursing students, which may be useful in conducting intervention strategies to avoid the negative consequences and reinforce the positive ones of this trait.

Exploring the similarities between risk factors triggering depression in humans and elevated in-cage "inactive but awake" behavior in laboratory mice

Introduction

Depression is a human mental disorder that can also be inferred in non-human animals. This study explored whether time spent inactive but awake ("IBA") in the home-cage in mice was further triggered by risk factors similar to those increasing vulnerability to depression in humans (early life stress, genetic predispositions, adulthood stress).

Methods

Eighteen DBA/2 J and 18 C57BL/6 J females were tested, of which half underwent as pups a daily maternal separation on post-natal days 2-14 (early-life stress "ELS") (other half left undisturbed). To assess the effect of the procedure, the time the dams from which the 18 subjects were born spent active in the nest (proxy for maternal behavior) was recorded on post-natal days 2, 6, 10 and 14 for 1 h before separation and following reunion (matched times for controls), using live instantaneous scan sampling (total: 96 scans/dam). For each ELS condition, about half of the pups were housed post-weaning (i.e., from 27 days old on average) in either barren (triggering IBA and depression-like symptoms) or larger, highly enriched cages (n = 4-5 per group). Time mice spent IBA post-weaning was observed blind to ELS treatment using live instantaneous scan sampling in two daily 90-min blocks, two days/week, for 6 weeks (total: 192 scans/mouse). Data were analyzed in R using generalized linear mixed models.

Results

The dams were significantly more active in the nest over time (p = 0.016), however with no significant difference between strains (p = 0.18), ELS conditions (p = 0.20) and before/after separation (p = 0.83). As predicted, post-weaning barren cages triggered significantly more time spent IBA in mice than enriched cages (p < 0.0001). However, neither ELS (p = 0.4) nor strain (p = 0.84) significantly influenced time mice spent IBA, with no significant interaction with environmental condition (ELS × environment: p = 0.2861; strain × environment: p = 0.5713).

Discussion

Our results therefore only partly support the hypothesis that greater time spent IBA in mice is triggered by risk factors for human depression. We discuss possible explanations for this and further research directions.

Sex-dependent placental methylation quantitative trait loci provide insight into the prenatal origins of childhood onset traits and conditions

Molecular quantitative trait loci (QTLs) allow us to understand the biology captured in genome-wide association studies (GWASs). The placenta regulates fetal development and shows sex differences in DNA methylation. We therefore hypothesized that placental methylation QTL (mQTL) explain variation in genetic risk for childhood onset traits, and that effects differ by sex. We analyzed 411 term placentas from two studies and found 49,252 methylation (CpG) sites with mQTL and 2,489 CpG sites with sex-dependent mQTL. All mQTL were enriched in regions that typically affect gene expression in prenatal tissues. All mQTL were also enriched in GWAS results for growth- and immune-related traits, but male- and female-specific mQTL were more enriched than cross-sex mQTL. mQTL colocalized with trait loci at 777 CpG sites, with 216 (28%) specific to males or females. Overall, mQTL specific to male and female placenta capture otherwise overlooked variation in childhood traits.

Central role of the habenulo-interpeduncular system in the neurodevelopmental basis of susceptibility and resilience to anxiety in mice

Having experienced stress during sensitive periods of brain development strongly influences how individuals cope with later stress. Some are prone to develop anxiety or depression, while others appear resilient. The as-yet-unknown mechanisms underlying these differences may lie in how genes and environmental stress interact to shape the circuits that control emotions. Here, we investigated the role of the habenulo-interpeduncular system (HIPS), a critical node in reward circuits, in early stress-induced anxiety in mice. We found that habenular and IPN components characterized by the expression of Otx2 are synaptically connected and particularly sensitive to chronic stress (CS) during the peripubertal period. Stress-induced peripubertal activation of this HIPS subcircuit elicits both HIPS hypersensitivity to later stress and susceptibility to develop anxiety. We also show that HIPS silencing through conditional Otx2 knockout counteracts these effects of stress. Together, these results demonstrate that a genetic factor, Otx2, and stress interact during the peripubertal period to shape the stress sensitivity of the HIPS, which is shown to be a key modulator of susceptibility or resilience to develop anxiety.

Enhanced polygenic risk score incorporating gene-environment interaction suggests the association of major depressive disorder with cardiac and lung function

BACKGROUND

Depression has been linked to an increased risk of cardiovascular and respiratory diseases; however, its impact on cardiac and lung function remains unclear, especially when accounting for potential gene-environment interactions.

METHODS

We developed a novel polygenic and gene-environment interaction risk score (PGIRS) integrating the major genetic effect and gene-environment interaction effect of depression-associated loci. The single nucleotide polymorphisms (SNPs) demonstrating major genetic effect or environmental interaction effect were obtained from genome-wide SNP association and SNP-environment interaction analyses of depression. We then calculated the depression PGIRS for non-depressed individuals, using smoking and alcohol consumption as environmental factors. Using linear regression analysis, we assessed the associations of PGIRS and conventional polygenic risk score (PRS) with lung function (N = 42 886) and cardiac function (N = 1791) in the subjects with or without exposing to smoking and alcohol drinking.

RESULTS

We detected significant associations of depression PGIRS with cardiac and lung function, contrary to conventional depression PRS. Among smokers, forced vital capacity exhibited a negative association with PGIRS (β = -0.037, FDR = 1.00 × 10-8), contrasting with no significant association with PRS (β = -0.002, FDR = 0.943). In drinkers, we observed a positive association between cardiac index with PGIRS (β = 0.088, FDR = 0.010), whereas no such association was found with PRS (β = 0.040, FDR = 0.265). Notably, in individuals who both smoked and drank, forced expiratory volume in 1-second demonstrated a negative association with PGIRS (β = -0.042, FDR = 6.30 × 10-9), but not with PRS (β = -0.003, FDR = 0.857).

CONCLUSIONS

Our findings underscore the profound impact of depression on cardiac and lung function, highlighting the enhanced efficacy of considering gene-environment interactions in PRS-based studies.

New insights into the physiology and pathophysiology of the atypical sodium leak channel NALCN

Cell excitability and its modulation by hormones and neurotransmitters involve the concerted action of a large repertoire of membrane proteins, especially ion channels. Unique complements of coexpressed ion channels are exquisitely balanced against each other in different excitable cell types, establishing distinct electrical properties that are tailored for diverse physiological contributions, and dysfunction of any component may induce a disease state. A crucial parameter controlling cell excitability is the resting membrane potential (RMP) set by extra- and intracellular concentrations of ions, mainly Na+, K+, and Cl-, and their passive permeation across the cell membrane through leak ion channels. Indeed, dysregulation of RMP causes significant effects on cellular excitability. This review describes the molecular and physiological properties of the Na+ leak channel NALCN, which associates with its accessory subunits UNC-79, UNC-80, and NLF-1/FAM155 to conduct depolarizing background Na+ currents in various excitable cell types, especially neurons. Studies of animal models clearly demonstrate that NALCN contributes to fundamental physiological processes in the nervous system including the control of respiratory rhythm, circadian rhythm, sleep, and locomotor behavior. Furthermore, dysfunction of NALCN and its subunits is associated with severe pathological states in humans. The critical involvement of NALCN in physiology is now well established, but its study has been hampered by the lack of specific drugs that can block or agonize NALCN currents in vitro and in vivo. Molecular tools and animal models are now available to accelerate our understanding of how NALCN contributes to key physiological functions and the development of novel therapies for NALCN channelopathies.

The Heritability of Psychopathology Symptoms in Early Adolescence: Moderation by Family Cultural Values in the ABCD Study

Family cultural values that emphasize support, loyalty, and obligation to the family are associated with lower psychopathology in Hispanic/Latino/a youth, but there is a need to understand the implications of family cultural values for youth development in racially/ethnically heterogeneous samples. This study examined phenotypic associations between parent- and youth-reported family cultural values in late childhood on youth internalizing and externalizing symptoms in early adolescence, and whether family cultural values moderated genetic and environmental influences on psychopathology symptoms. The sample comprised 10,335 children (Mage=12.89 years; 47.9% female; 20.3% Hispanic/Latino/a, 15.0% Black, 2.1% Asian, 10.5% other) and their parents from the Adolescent Brain Cognitive Development (ABCD) Study, and biometric models were conducted in the twin subsample (n = 1,042 twin pairs; 43.3% monozygotic). Parents and youth reported on their family cultural values using the Mexican American Cultural Values Scale at youth age 11-12, and parents reported on youth internalizing and externalizing symptoms using the Child Behavior Checklist at youth ages 11-12 and 12-13. Greater parent- and youth-reported family cultural values predicted fewer youth internalizing and externalizing symptoms. Biometric models indicated that higher parent-reported family cultural values increased the nonshared environmental influences on externalizing symptoms whereas youth-reported family cultural values decreased the nonshared environmental influences on internalizing symptoms. This study highlights the need for behavior genetic research to consider a diverse range of cultural contexts to better understand the etiology of youth psychopathology.

Genotype-environment interplay in associations between maternal drinking and offspring emotional and behavioral problems

BACKGROUND

While maternal at-risk drinking is associated with children's emotional and behavioral problems, there is a paucity of research that properly accounts for genetic confounding and gene-environment interplay. Therefore, it remains uncertain what mechanisms underlie these associations. We assess the moderation of associations between maternal at-risk drinking and childhood emotional and behavioral problems by common genetic variants linked to environmental sensitivity (genotype-by-environment [G × E] interaction) while accounting for shared genetic risk between mothers and offspring (GE correlation).

METHODS

We use data from 109 727 children born to 90 873 mothers enrolled in the Norwegian Mother, Father, and Child Cohort Study. Women self-reported alcohol consumption and reported emotional and behavioral problems when children were 1.5/3/5 years old. We included child polygenic scores (PGSs) for traits linked to environmental sensitivity as moderators.

RESULTS

Associations between maternal drinking and child emotional (β1 = 0.04 [95% confidence interval (CI) 0.03-0.05]) and behavioral (β1 = 0.07 [0.06-0.08]) outcomes attenuated after controlling for measured confounders and were almost zero when we accounted for unmeasured confounding (emotional: β1 = 0.01 [0.00-0.02]; behavioral: β1 = 0.01 [0.00-0.02]). We observed no moderation of these adjusted exposure effects by any of the PGS.

CONCLUSIONS

The lack of strong evidence for G × E interaction may indicate that the mechanism is not implicated in this kind of intergenerational association. It may also reflect insufficient power or the relatively benign nature of the exposure in this sample.

Exploring Mental Health Awareness: A Study on Knowledge and Perceptions of Mental Health Disorders among Residents of Matsafeni Village, Mbombela, Mpumalanga Province

The global rise in mental health disorders has significant social, economic, and physical impacts. Despite advancements in support, cultural beliefs attributing mental illnesses to spiritual causes persist, fostering discrimination and stigmatization. The study aims to explore the understanding and perceptions of mental health in Matsafeni Village, acknowledging the complexity of mental health issues. A qualitative method and a descriptive exploratory design were employed, enabling the researcher to describe, examine, and explore the knowledge and perceptions regarding mental health. Data collection was conducted through unstructured, open-ended interviews, with 15 participants selected through convenience sampling. The data were analyzed through thematic analysis. Measures of rigor were ensured through credibility, transferability, confirmability, and dependability. Participants demonstrated knowledge of mental health disorders, recognizing disruptions in thought patterns and diverse symptoms. They highlighted key signs and behaviors, emphasizing the need for spotting indicators such as untidiness. Perceptions of the causes of mental illness varied, including witchcraft and genetics. Participants unanimously advocated for seeking help from traditional healers, medical facilities, and therapies. Community members shared their views of mental health, covering their understanding, recognition of signs, personal interactions, and observations of behaviors in individuals with mental health conditions. Reported symptoms align with existing research, emphasizing the complexity of managing safety concerns in severe mental illnesses. The study highlights the need for community education to reduce stigma, considering cultural factors in mental health perceptions. Recommendations include early interventions, enhanced mental health services, and collaboration between western and traditional approaches for a holistic and culturally sensitive approach to mental health.

A multidimensional social risk atlas of depression and anxiety: An observational and genome-wide environmental interaction study

Background

Mental disorders are largely socially determined, yet the combined impact of multidimensional social factors on the two most common mental disorders, depression and anxiety, remains unclear.

Methods

We constructed a polysocial risk score (PsRS), a multidimensional social risk indicator including components from three domains: socioeconomic status, neighborhood and living environment and psychosocial factors. Supported by the UK Biobank cohort, we randomly divided 110 332 participants into the discovery cohort (60%; n = 66 200) and the replication cohort (40%; n = 44 134). We tested the associations between 13 single social factors with Patient Health Questionnaire (PHQ) score, Generalized Anxiety Disorder Scale (GAD) score and self-reported depression and anxiety. The significant social factors were used to calculate PsRS for each mental disorder by considering weights from the multivariable linear model. Generalized linear models were applied to explore the association between PsRS and depression and anxiety. Genome-wide environmental interaction study (GWEIS) was further performed to test the effect of interactions between PsRS and SNPs on the risk of mental phenotypes.

Results

In the discovery cohort, PsRS was positively associated with PHQ score (β = 0.37; 95% CI = 0.35-0.38), GAD score (β = 0.27; 95% CI = 0.25-0.28), risk of self-reported depression (OR = 1.29; 95% CI = 1.28-1.31) and anxiety (OR = 1.19; 95% CI = 1.19-1.23). Similar results were observed in the replication cohort. Emotional stress, lack of social support and low household income were significantly associated with the development of depression and anxiety. GWEIS identified multiple candidate loci for PHQ score, such as rs149137169 (ST18) (Pdiscovery = 1.08 × 10-8, Preplication = 3.25 × 10-6) and rs3759812 (MYO9A) (Pdiscovery = 3.87 × 10-9, Preplication = 6.21 × 10-5). Additionally, seven loci were detected for GAD score, such as rs114006170 (TMPRSS11D) (Pdiscovery = 1.14 × 10-9, Preplication = 7.36 × 10-5) and rs77927903 (PIP4K2A) (Pdiscovery = 2.40 × 10-9, Preplication = 0.002).

Conclusions

Our findings reveal the positive effects of multidimensional social factors on the risk of depression and anxiety. It is important to address key social disadvantage in mental health promotion and treatment.

A Wolf in Sheep's Clothing: Idealisations and the aims of polygenic scores

Research in pharmacogenomics and precision medicine has recently introduced the concept of Polygenic Scores (PGSs), namely, indexes that aggregate the effects that many genetic variants are predicted to have on individual disease risk. The popularity of PGSs is increasing rapidly, but surprisingly little attention has been paid to the idealisations they make about phenotypic development. Indeed, PGSs rely on quantitative genetics models and methods, which involve considerable theoretical assumptions that have been questioned on various grounds. This comes with epistemological and ethical concerns about the use of PGSs in clinical decision-making. In this paper, I investigate to what extent idealisations in genetics models can impact the data gathering and clinical interpretation of genomics findings, particularly the calculation and predictive accuracy of PGSs. Although idealisations are considered ineliminable components of scientific models, they may be legitimate or not depending on the epistemic aims of a model. I thus analyse how various idealisations have been introduced in classical models and progressively readapted throughout the history of genetic theorising. Notably, this process involved important changes in the epistemic purpose of such idealisations, which raises the question of whether they are legitimate in the context of contemporary genomics.

Association of polygenic scores for depression and neuroticism with perceived stress in daily life during a long-lasting stress period

Genetic factors contribute significantly to interindividual differences in the susceptibility to stress-related disorders. As stress can also be conceptualized as environmental exposure, controlled gene-environment interaction (GxE) studies with an in-depth phenotyping may help to unravel mechanisms underlying the interplay between genetic factors and stress. In a prospective-longitudinal quasi-experimental study, we investigated whether polygenic scores (PGS) for depression (DEP-PGS) and neuroticism (NEU-PGS), respectively, were associated with responses to chronic stress in daily life. We examined law students (n = 432) over 13 months. Participants in the stress group experienced a long-lasting stress phase, namely the preparation for the first state examination for law students. The control group consisted of law students without particular stress exposure. In the present manuscript, we analyzed perceived stress levels assessed at high frequency and in an ecologically valid manner by ambulatory assessments as well as depression symptoms and two parameters of the cortisol awakening response. The latter was only assessed in a subsample (n = 196). No associations between the DEP-PGS and stress-related variables were found. However, for the NEU-PGS we found a significant GxE effect. Only in individuals experiencing academic stress a higher PGS for neuroticism predicted stronger increases of perceived stress levels until the exam. At baseline, a higher NEU-PGS was associated with higher perceived stress levels in both groups. Despite the small sample size, we provide preliminary evidence that the genetic disposition for neuroticism is associated with stress level increases in daily life during a long-lasting stress period.

Gene-educational attainment interactions in a multi-population genome-wide meta-analysis identify novel lipid loci

Introduction: Educational attainment, widely used in epidemiologic studies as a surrogate for socioeconomic status, is a predictor of cardiovascular health outcomes. Methods: A two-stage genome-wide meta-analysis of low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), and triglyceride (TG) levels was performed while accounting for gene-educational attainment interactions in up to 226,315 individuals from five population groups. We considered two educational attainment variables: "Some College" (yes/no, for any education beyond high school) and "Graduated College" (yes/no, for completing a 4-year college degree). Genome-wide significant (p < 5 × 10-8) and suggestive (p < 1 × 10-6) variants were identified in Stage 1 (in up to 108,784 individuals) through genome-wide analysis, and those variants were followed up in Stage 2 studies (in up to 117,531 individuals). Results: In combined analysis of Stages 1 and 2, we identified 18 novel lipid loci (nine for LDL, seven for HDL, and two for TG) by two degree-of-freedom (2 DF) joint tests of main and interaction effects. Four loci showed significant interaction with educational attainment. Two loci were significant only in cross-population analyses. Several loci include genes with known or suggested roles in adipose (FOXP1, MBOAT4, SKP2, STIM1, STX4), brain (BRI3, FILIP1, FOXP1, LINC00290, LMTK2, MBOAT4, MYO6, SENP6, SRGAP3, STIM1, TMEM167A, TMEM30A), and liver (BRI3, FOXP1) biology, highlighting the potential importance of brain-adipose-liver communication in the regulation of lipid metabolism. An investigation of the potential druggability of genes in identified loci resulted in five gene targets shown to interact with drugs approved by the Food and Drug Administration, including genes with roles in adipose and brain tissue. Discussion: Genome-wide interaction analysis of educational attainment identified novel lipid loci not previously detected by analyses limited to main genetic effects.

Calcium Homeostasis and Psychiatric Disorders: A Mendelian Randomization Study

Observational studies have investigated the impact of calcium homeostasis on psychiatric disorders; however, the causality of associations is yet to be established. Bidirectional Mendelian randomization (MR) analysis of calcium homeostasis hormones was conducted on nine psychiatric disorders. Calcium, serum 25-hydroxyvitamin D levels (25OHD), parathyroid hormone, and fibroblast growth factor 23 are the major calcium homeostasis hormones. The causality was evaluated by the inverse variance weighted method (IVW) and the MR Steiger test, while Cochran's Q test, the MR-Egger intercept test, funnel plot, and the leave-one-out method were used for sensitivity analyses. Bonferroni correction was used to determine the causative association features (p < 6.94 × 10-4). Schizophrenia (SCZ) was significantly associated with decreased 25OHD concentrations with an estimated effect of -0.0164 (Prandom-effect IVW = 2.39 × 10-7). In the Multivariable MR (MVMR) analysis adjusting for potentially confounding traits including body mass index, obesity, mineral supplements (calcium, fish oil, and vitamin D) and outdoor time (winter and summer), the relationship between SCZ and 25OHD remained. The genetically predicted autism spectrum disorder and bipolar disorder were also nominally associated with decreased 25OHD. This study provided evidence for a causal effect of psychiatric disorders on calcium homeostasis. The clinical monitoring of 25OHD levels in patients with psychiatric disorders is beneficial.

Stress-mediated dysregulation of the Rap1 small GTPase impairs hippocampal structure and function

The effects of repeated stress on cognitive impairment are thought to be mediated, at least in part, by reductions in the stability of dendritic spines in brain regions critical for proper learning and memory, including the hippocampus. Small GTPases are particularly potent regulators of dendritic spine formation, stability, and morphology in hippocampal neurons. Through the use of small GTPase protein profiling in mice, we identify increased levels of synaptic Rap1 in the hippocampal CA3 region in response to escalating, intermittent stress. We then demonstrate that increased Rap1 in the CA3 is sufficient in and of itself to produce stress-relevant dendritic spine and cognitive phenotypes. Further, using super-resolution imaging, we investigate how the pattern of Rap1 trafficking to synapses likely underlies its effects on the stability of select dendritic spine subtypes. These findings illuminate the involvement of aberrant Rap1 regulation in the hippocampus in contributing to the psychobiological effects of stress.

Early-life stress contributes to depression-like behaviors in a two-hit mouse model

BACKGROUND

Depression is a common psychological disorder with pathogenesis involving genetic and environmental interactions. Early life stress can adversely affect physical and emotional development and dramatically increase the risk for the development of depression and anxiety disorders.

METHODS

To examine potential early life stress driving risk for anxiety and depression, we used a two-hit developmental stress model，injecting poly(I: C) into neonatal mice on P2-P6 followed by peripubertal unpredictable stress in adolescence.

RESULTS

Our study shows that early-life and adolescent stress leads to anxiety and depression-related behavioral phenotypes in male mice. Early-life stress exacerbated depression-like behavior in mice following peripubertal unpredictable stress. We confirmed that early life stress might be involved in the decreased neuronal activity in the medial prefrontal cortex (mPFC) and might be involved in shaping behavioral phenotypes of animals. We found that increased microglia and neuroinflammation in the mPFC of two-hit mice and early life stress further boost microglia activation and inflammatory factors in the mPFC region of mice following adolescent stress.

LIMITATIONS

The specific neural circuits and mechanisms by which microglia regulate depression-like behaviors require further investigation.

CONCLUSIONS

Our findings provide a novel insight into developmental risk factors and biological mechanisms in depression and anxiety disorders.

Comparative neurogenetics of dog behavior complements efforts towards human neuropsychiatric genetics

Domestic dogs display a wide array of heritable behaviors that have intermediate genetic complexity thanks to a long history of human-influenced selection. Comparative genetics in dogs could address the scarcity of non-human neurogenetic systems relevant to human neuropsychiatric disorders, which are characterized by mental, emotional, and behavioral symptoms and involve vastly complex genetic and non-genetic risk factors. Our review describes the diverse behavioral "phenome" of domestic dogs, past and ongoing sources of behavioral selection, and the state of canine behavioral genetics. We highlight two naturally disordered behavioral domains that illustrate how dogs may prove useful as a comparative, forward neurogenetic system: canine age-related cognitive dysfunction, which can be examined more rapidly given the attenuated lifespan of dogs, and compulsive disorders, which may have genetic roots in purpose-bred behaviors. Growing community science initiatives aimed at the companion dog population will be well suited to investigating such complex behavioral phenotypes and offer a comparative resource that parallels human genomic initiatives in scale and dimensionality.

A person-centered data analytic approach to dopaminergic polygenic moderation of child maltreatment exposure

The present study illustrates the utility of latent class analysis, a person-centered data analytic approach, as an innovative method for identifying naturally occurring patterns of polygenic risk, specifically within the dopaminergic system. Moreover, this study tests whether latent classes of polygenic variation moderate the effect of child maltreatment exposure on internalizing symptoms among African ancestry youth. African ancestry youth were selected for this study because youth of color are overrepresented in the child welfare system and because African ancestry individuals are significantly underrepresented in genomics research. Results identified three latent classes of dopaminergic gene variation. Class 1 was marked predominately by homozygous minor alleles, Class 2 was characterized by homozygous major and heterozygous presentations, and Class 3 was marked by heterozygous alleles on the DAT-1 single-nucleotide polymorphisms (SNPs) and a combination of homozygous major and minor alleles on the other SNPs. Results indicated that a greater number of maltreatment subtypes experienced were associated with higher internalizing symptoms only for children with the latent polygenic Class 2 pattern. This latent class was distinctly characterized by more homozygous major or heterozygous allelic presentations along all three DAT-1 SNPs. This significant latent polygenic class by environment interaction was replicated in an independent replication sample. Together, findings suggest that African ancestry children with a pattern of dopaminergic variation characterized by this specific combination of polygenic variation are more vulnerable to developing internalizing symptoms following maltreatment exposure, relative to their peers with other dopamine-related polygenic patterns.

Polygenic and environmental determinants of tics in the Avon Longitudinal Study of Parents and Children

Tourette syndrome (TS) is caused by multiple genetic and environmental factors. Yet, little is known about the interplay of these factors in the occurrence of tics. We investigated whether polygenic risk score (PRS) of TS and pregnancy-related factors together enhance the explained variance of tic occurrence in the Avon Longitudinal Study of Parents and Children (Ncases  = 612; Ncontrols  = 4,201; 50% male; mean age 13.8 years). We included a cumulative adverse pregnancy risk score, maternal anxiety and depression, and maternal smoking and alcohol use during pregnancy. We investigated possible joint effects of genetic and pregnancy-related risk factors using a multivariable approach, and explored mediation effects between the pregnancy-related risk factors in explaining tic presence. The PRS and the cumulative adverse pregnancy risk score, maternal anxiety, or maternal depression explained significantly more variance of tic presence compared to models including only the PRS. Furthermore, we found that the cumulative adverse pregnancy risk score mediated the association between several pregnancy-related factors (maternal anxiety, depression, and smoking) and tics. The combination of a PRS and pregnancy-related risk factors explained more variance of tics in a general population cohort compared to studying these factors in isolation.

Link between cognitive polygenic risk scores and clinical progression after a first-psychotic episode

BACKGROUND

Clinical intervention in early stages of psychotic disorders is crucial for the prevention of severe symptomatology trajectories and poor outcomes. Genetic variability is studied as a promising modulator of prognosis, thus novel approaches considering the polygenic nature of these complex phenotypes are required to unravel the mechanisms underlying the early progression of the disorder.

METHODS

The sample comprised of 233 first-episode psychosis (FEP) subjects with clinical and cognitive data assessed periodically for a 2-year period and 150 matched controls. Polygenic risk scores (PRSs) for schizophrenia, bipolar disorder, depression, education attainment and cognitive performance were used to assess the genetic risk of FEP and to characterize their association with premorbid, baseline and progression of clinical and cognitive status.

RESULTS

Schizophrenia, bipolar disorder and cognitive performance PRSs were associated with an increased risk of FEP [false discovery rate (FDR) ⩽ 0.027]. In FEP patients, increased cognitive PRSs were found for FEP patients with more cognitive reserve (FDR ⩽ 0.037). PRSs reflecting a genetic liability for improved cognition were associated with a better course of symptoms, functionality and working memory (FDR ⩽ 0.039). Moreover, the PRS of depression was associated with a worse trajectory of the executive function and the general cognitive status (FDR ⩽ 0.001).

CONCLUSIONS

Our study provides novel evidence of the polygenic bases of psychosis and its clinical manifestation in its first stage. The consistent effect of cognitive PRSs on the early clinical progression suggests that the mechanisms underlying the psychotic episode and its severity could be partially independent.

Gene-by-Environment Interaction Effects of Social Adversity on Externalizing Behavior in ABCD Youth

This study tested whether multiple domains of social adversity, including neighborhood opportunity/deprivation and life stress, moderate genetic (A), common environmental (C), and unique environmental (E) influences on externalizing behaviors in 760 same-sex twin pairs (332 monozygotic; 428 dizygotic) ages 10-11 from the ABCD Study. Proportion of C influences on externalizing behavior increased at higher neighborhood adversity (lower overall opportunity). A decreased and C and E increased at lower levels of educational opportunity. A increased at lower health-environment and social-economic opportunity levels. For life stress, A decreased and E increased with number of experienced events. Results for educational opportunity and stressful life experiences suggest a bioecological gene-environment interaction pattern such that environmental influences predominate at higher levels of adversity, whereas limited access to healthcare, housing, and employment stability may potentiate genetic liability for externalizing behavior via a diathesis-stress mechanism. More detailed operationalization of social adversity in gene-environment interaction studies is needed.

Exposure to alcohol outlets and risk of suicidal behavior in a Swedish cohort of young adults

BACKGROUND

Greater alcohol accessibility, for example in the form of a high density of alcohol outlets or low alcohol taxation rates, may be associated with increased risk of suicidal behavior. However, most studies have been conducted at the aggregate level, and some have not accounted for potential confounders such as socioeconomic position or neighborhood quality.

METHODS

In a Swedish cohort of young adults aged 18 to 25, we used logistic regressions to evaluate whether living in a neighborhood that included bars, nightclubs, and/or government alcohol outlets was associated with risk of suicide attempt (SA) or suicide death (SD) during four separate 2-year observation periods. Neighborhoods were defined using pre-established nationwide designations. We conducted combined-sex and sex-stratified analyses, and included as covariates indicators of socioeconomic position, neighborhood deprivation, and aggregate genetic liability to suicidal behavior.

RESULTS

Risk of SA was increased in some subsamples of individuals living in a neighborhood with a bar or government alcohol outlet (odds ratios [ORs] = 1.05 to 1.15). Risk of SD was also higher among certain subsamples living in a neighborhood with a government outlet (ORs = 1.47 to 1.56), but lower for those living near a bar (ORs = 0.89 to 0.91). Significant results were driven by, but not exclusive to, the male subsample. Individuals with higher aggregate genetic risk for SA were more sensitive to the effects of a neighborhood government alcohol outlet, pooled across observation periods, in analyses of the sexes combined (relative excess risk due to interaction [RERI] = 0.05; 95% confidence intervals [CI] 0.01; 0.09) and in the male subsample (RERI = 0.06; 95% CI 0.001; 0.12).

CONCLUSIONS

Although effect sizes are small, living in a neighborhood with bars and/or government alcohol outlets may increase suicidal behavior among young adults. Individuals with higher genetic liability for SA are slightly more susceptible to these exposures.

Genome-Environment Interactions and Psychiatric Disorders

Environmental factors are known to interact with the genome by altering epigenetic mechanisms regulating gene expression and contributing to the pathogenesis of psychiatric disorders. This article is a narrative review of how the major environmental factors contribute to the pathogenesis of common psychiatric disorders such as schizophrenia, bipolar disorder, major depressive disorder, and anxiety disorder this way. The cited articles were published between 1 January 2000 and 31 December 2022 and were obtained from PubMed and Google Scholar. The search terms used were as follows: gene or genetic; genome; environment; mental or psychiatric disorder; epigenetic; and interaction. The following environmental factors were found to act epigenetically on the genome to influence the pathogenesis of psychiatric disorders: social determinants of mental health, maternal prenatal psychological stress, poverty, migration, urban dwelling, pregnancy and birth complications, alcohol and substance abuse, microbiota, and prenatal and postnatal infections. The article also discusses the ways by which factors such as drugs, psychotherapy, electroconvulsive therapy, and physical exercise act epigenetically to alleviate the symptoms of psychiatric disorders in affected patients. These data will be useful information for clinical psychiatrists and those researching the pathogenesis and treatment of psychiatric disorders.

Child maltreatment and health service use: findings of the Australian Child Maltreatment Study

OBJECTIVES

To examine associations between child maltreatment and health service use, both overall, by type and by the number of types of maltreatment reported.

DESIGN, SETTING

Cross-sectional, retrospective survey using the Juvenile Victimization Questionnaire-R2: Adapted Version (Australian Child Maltreatment Study); computer-assisted mobile telephone interviews using random digit dialling, Australia, 9 April - 11 October 2021.

PARTICIPANTS

Australians aged 16 years or more. The target sample size was 8500 respondents: 3500 people aged 16-24 years and 1000 respondents each from the five age groups (25-34, 35-44, 45-54, 55-64, 65 years or more).

MAIN OUTCOME MEASURES

Self-reported health service use during the past twelve months: hospital admissions, length of stay, and reasons for admission; and numbers of consultations with health care professionals, overall and by type. Associations between maltreatment and health service use are reported as odds ratios adjusted for age group, gender, socio-economic status, financial hardship (childhood and current), and geographic remoteness.

RESULTS

A total of 8503 participants completed the survey. Respondents who had experienced child maltreatment were significantly more likely than those who had not to report a hospital admission during the preceding twelve months (adjusted odds ratio [aOR], 1.39; 95% confidence interval [CI], 1.16-1.66), particularly admission with a mental disorder (aOR, 2.4; 95% CI, 1.03-5.6). The likelihood of six or more visits to general practitioners (aOR, 2.37; 95% CI, 1.87-3.02) or of a consultation with a mental health nurse (aOR, 2.67; 95% CI, 1.75-4.06), psychologist (aOR, 2.40; 95% CI, 2.00-2.88), or psychiatrist (aOR, 3.02; 95% CI, 2.25-4.04) were each higher for people who reported maltreatment during childhood. People who reported three or more maltreatment types were generally most likely to report greater health service use.

CONCLUSIONS

Child maltreatment has a major impact on health service use. Early, targeted interventions are vital, not only for supporting children directly, but also for their longer term wellbeing and reducing their health system use throughout life.

Do Poor Diet and Lifestyle Behaviors Modify the Genetic Susceptibility to Impulsivity in the General Population?

The present study investigated whether an unhealthy diet and other lifestyle behaviors may modify the genetic susceptibility to impulsivity. A total of 33,047 participants (mean age = 42.1 years, 59.8% females) from the Dutch Lifelines cohort were included. Each diet index and other lifestyle behaviors were tested for their interactions on the effect on the attention-deficit/hyperactivity disorder (ADHD) polygenic risk score (PRS) on impulsivity using a linear regression model with adjustment for covariates. The ADHD PRS was significantly associated with impulsivity (B = 0.03 (95% CI: 0.02, 0.04); p = 2.61 × 10−9). A poorer diet, a higher intake of energy, and a higher intake of fat were all associated with higher impulsivity, and a high intake of energy amplified the effect of ADHD PRS on impulsivity (e.g., for the interaction term of ADHD PRS and highest tertile on intake of energy, B = 0.038 (95% CI: 0.014, 0.062); p = 0.002. The other lifestyle factors, namely short and long sleep duration, current and past smoking, higher alcohol intake, and more time spent on moderate-to-vigorous physical activity were associated with higher impulsivity, but no interaction effect was observed. In conclusion, we found that a high intake of energy exacerbated the genetic susceptibility to impulsivity. Our study helps to improve our understanding of the role of diet and genetic factors on impulsivity.

A comparison of stress reactivity between BTBR and C57BL/6J mice: an impact of early-life stress

Early-life stress (ELS) is associated with hypothalamic-pituitary-adrenal (HPA) axis dysregulation and can increase the risk of psychiatric disorders later in life. The aim of this study was to investigate the influence of ELS on baseline HPA axis functioning and on the response to additional stress in adolescent male mice of strains C57BL/6J and BTBR. As a model of ELS, prolonged separation of pups from their mothers (for 3 h once a day: maternal separation [MS]) was implemented. To evaluate HPA axis activity, we assessed serum corticosterone levels and mRNA expression of corticotropin-releasing hormone (Crh) in the hypothalamus, of steroidogenesis genes in adrenal glands, and of an immediate early gene (c-Fos) in both tissues at baseline and immediately after 1 h of restraint stress. HPA axis activity at baseline did not depend on the history of ELS in mice of both strains. After the exposure to the acute restraint stress, C57BL/6J-MS mice showed less pronounced upregulation of Crh and of corticosterone concentration as compared to the control, indicating a decrease in stress reactivity. By contrast, BTBR-MS mice showed stronger upregulation of c-Fos in the hypothalamus and adrenal glands as compared to controls, thus pointing to greater activation of these organs in response to the acute restraint stress. In addition, we noted that BTBR mice are more stress reactive (than C57BL/6J mice) because they exhibited greater upregulation of corticosterone, c-Fos, and Cyp11a1 in response to the acute restraint stress. Taken together, these results indicate strain-specific and situation-dependent effects of ELS on HPA axis functioning and on c-Fos expression.

The interactive association of adverse childhood experiences and polygenic susceptibility with depressive symptoms and chronic inflammation in older adults: a prospective cohort study

BACKGROUND

Adverse childhood experiences (ACEs) and genetic liability are important risk factors for depression and inflammation. However, little is known about the gene-environment (G × E) mechanisms underlying their aetiology. For the first time, we tested the independent and interactive associations of ACEs and polygenic scores of major depressive disorder (MDD-PGS) and C-reactive protein (CRP-PGS) with longitudinal trajectories of depression and chronic inflammation in older adults.

METHODS

Data were drawn from the English longitudinal study of ageing (N~3400). Retrospective information on ACEs was collected in wave3 (2006/07). We calculated a cumulative risk score of ACEs and also assessed distinct dimensions separately. Depressive symptoms were ascertained on eight occasions, from wave1 (2002/03) to wave8 (2016/17). CRP was measured in wave2 (2004/05), wave4 (2008/09), and wave6 (2012/13). The associations of the risk factors with group-based depressive-symptom trajectories and repeated exposure to high CRP (i.e. ⩾3 mg/L) were tested using multinomial and ordinal logistic regression.

RESULTS

All types of ACEs were independently associated with high depressive-symptom trajectories (OR 1.44, 95% CI 1.30-1.60) and inflammation (OR 1.08, 95% CI 1.07-1.09). The risk of high depressive-symptom trajectories (OR 1.47, 95% CI 1.28-1.70) and inflammation (OR 1.03, 95% CI 1.01-1.04) was also higher for participants with higher MDD-PGS. G×E analyses revealed that the associations between ACEs and depressive symptoms were larger among participants with higher MDD-PGS (OR 1.13, 95% CI 1.04-1.23). ACEs were also more strongly related to inflammation in participants with higher CRP-PGS (OR 1.02, 95% CI 1.01-1.03).

CONCLUSIONS

ACEs and polygenic susceptibility were independently and interactively associated with elevated depressive symptoms and chronic inflammation, highlighting the clinical importance of assessing both ACEs and genetic risk factors to design more targeted interventions.