Discoidin domain receptor 1 gene variants are associated with decreased white matter fractional anisotropy and decreased processing speed in schizophrenia.

Abstract DDR1 has been linked to schizophrenia (SZ) and myelination. Here, we tested whether DDR1 variants in people at risk for SZ influence white matter (WM) structural variations and cognitive processing speed (PS). First, following a case-control design (Study 1), SZ patients (N = 1193) and controls (N = 1839) were genotyped for rs1264323 and rs2267641 at DDR1, and the frequencies were compared. We replicated the association between DDR1 and SZ (rs1264323, adjusted P = 0.015). Carriers of the rs1264323AA combined with the rs2267641AC or CC genotype are at risk to develop SZ compared to the other genotype combinations. Second, SZ patients (Study 2, N = 194) underwent an evaluation of PS …

Research Letter: is neuroticism a risk factor for postpartum depression?

Although the relationship between personality and depressive illness is complex (Shea, 2005), there is empirical evidence that some personality features such as neuroticism, harm avoidance, introversion, dependency, self-criticism or perfectionism are related to depressive illness risk (Gunderson et al. 1999). Moreover, personality traits, especially neuroticism, may explain the increased prevalence of depression among females (Goodwin & Gotlib, 2004). Few studies have explored neuroticism, extraversion and psychoticism as risk factors for depression after an event as stressful as childbirth. Pitt (1968) was the first author to report high scores on neuroticism and low scores on extraversio…

The EUropean Network of National Schizophrenia Networks Studying Gene-Environment Interactions (EU-GEI)

Funder: FP7 Ideas: European Research Council; doi: http://dx.doi.org/10.13039/100011199; Grant(s): HEALTH-F2-2010-241909

Association Study of Nonsynonymous Single Nucleotide Polymorphisms in Schizophrenia

Genome-wide association studies using several hundred thousand anonymous markers present limited statistical power. Alternatively, association studies restricted to common nonsynonymous single nucleotide polymorphisms (nsSNPs) have the advantage of strongly reducing the multiple testing problem, while increasing the probability of testing functional single nucleotide polymorphisms (SNPs).We performed a case-control association study of common nsSNPs in Galician (northwest Spain) samples using the Affymetrix GeneChip Human 20k cSNP Kit, followed by a replication study of the more promising results. After quality control procedures, the discovery sample consisted of 5100 nsSNPs at minor allel…

A polygenic approach to the association between smoking and schizophrenia.

Smoking prevalence in schizophrenia is considerably larger than in general population, playing an important role in early mortality. We compared the polygenic contribution to smoking in schizophrenic patients and controls to assess if genetic factors may explain the different prevalence. Polygenic risk scores (PRSs) for smoking initiation and four genetically correlated traits were calculated in 1108 schizophrenic patients (64.4% smokers) and 1584 controls (31.1% smokers). PRSs for smoking initiation, educational attainment, body mass index and age at first birth were associated with smoking in patients and controls, explaining a similar percentage of variance in both groups. Attention-defi…

Rapid evolving RNA gene HAR1A and schizophrenia

Treated Incidence of Psychotic Disorders in the Multinational EU-GEI Study

Importance: Psychotic disorders contribute significantly to the global disease burden, yet the latest international incidence study of psychotic disorders was conducted in the 1980s. Objectives: To estimate the incidence of psychotic disorders using comparable methods across 17 catchment areas in 6 countries and to examine the variance between catchment areas by putative environmental risk factors. Design, Setting, and Participants: An international multisite incidence study (the European Network of National Schizophrenia Networks Studying Gene-Environment Interactions) was conducted from May 1, 2010, to April 1, 2015, among 2774 individuals from England (2 catchment areas), France (3 catch…

Potential involvement of serotonin receptor genes with age of onset and gender in schizophrenia: a preliminary study in a Spanish sample.

Association study of 44 candidate genes with depressive and anxiety symptoms in post-partum women.

The post-partum period is a time of extreme vulnerability for a whole spectrum of psychiatric disorders. Delivery may be considered an important risk factor in genetically susceptible women. Five hundred and eight SNPs in 44 genes at candidate pathways putatively related to mood changes after delivery were genotyped in a multicenter cohort of 1804 women from Spain. Participants completed two scales at 2-3 days, 8 weeks, and 32 weeks post-partum, the Edinburgh Post-partum Depression Scale (EPDS) and the Spielberger State-Trait Anxiety Inventory (STAI). Those women who scored 9 or more on EPDS were evaluated for major depression using the Diagnostic Interview for Genetics Studies (DIGS) adapt…

Coping strategies and postpartum depressive symptoms: A structural equation modelling approach.

AbstractBackgroundVariables such as the mother's personality, social support, coping strategies and stressful events have been described as risk factors for postpartum depression. Structural Equation Modelling (SEM) analysis was used to examine whether neuroticism, perceived social support, perceived life events, and coping strategies are associated with postpartum depressive symptoms at the 8th and 32nd weeks.MethodsA total of 1626 pregnant women participated in a longitudinal study. Different evaluations were performed 8 and 32 weeks after delivery. Several measures were used: the Edinburgh Postnatal Depression Scale (EPDS), the Diagnostic Interview for Genetic Studies (DIGS), the Eysenck…

Replication of previous genome-wide association studies of psychiatric diseases in a large schizophrenia case-control sample from Spain.

Genome wide association studies (GWAS) has allowed the discovery of some interesting risk variants for schizophrenia (SCZ). However, this high-throughput approach presents some limitations, being the most important the necessity of highly restrictive statistical corrections as well as the loss of statistical power inherent to the use of a Single Nucleotide Polymorphism (SNP) analysis approach. These problems can be partially solved through the use of a polygenic approach. We performed a genotyping study in SCZ using 86 previously associated SNPs identified by GWAS of SCZ, bipolar disorder (BPD) and autistic spectrum disorder (ASD) patients. The sample consisted of 3063 independent cases wit…

Consumo de substancias durante el embarazo y dimensiones de personalidad

Este estudio evalúa los patrones de consumo de substancias durante el embarazo y las dimensiones de personalidad asociadas, en una muestra multicéntrica de 1804 mujeres de población general. En el 2-3 día posparto, completaron una entrevista auto-administrada sobre el consumo de alcohol, tabaco, cafeína, cannabis, cocaína, opiáceos, drogas de diseño, además de variables socio-demográficas, obstétricas/reproductivas, historia psiquiátrica previa, apoyo social durante el embarazo y el cuestionario de personalidad de Eysenck (EPQ-RS). Se generaron modelos de regresión logística múltiple. La prevalencia del consumo fue del 50% (N=909): 40% cafeína, 21% tabaco, 3,5% alcohol, y 0,3 cannabis. Las …

The contribution of cannabis use to variation in the incidence of psychotic disorder across Europe (EU-GEI): a multicentre case-control study.

Background: Cannabis use is associated with increased risk of later psychotic disorder but whether it affects incidence of the disorder remains unclear. We aimed to identify patterns of cannabis use with the strongest effect on odds of psychotic disorder across Europe and explore whether differences in such patterns contribute to variations in the incidence rates of psychotic disorder. Methods: We included patients aged 18–64 years who presented to psychiatric services in 11 sites across Europe and Brazil with first-episode psychosis and recruited controls representative of the local populations. We applied adjusted logistic regression models to the data to estimate which patterns of canna…

The continuity of effect of schizophrenia polygenic risk score and patterns of cannabis use on transdiagnostic symptom dimensions at first-episode psychosis: findings from the EU-GEI study

The work was supported by Guarantors of Brain post-doctoral clinical fellowship to DQ; Clinician Scientist Medical Research Council fellowship (project reference MR/M008436/1) to MDF; Heisenberg professorship from the German Research Founda- tion (grant no. 389624707) to UR; the National Institute for Health Research (NIHR) Maudsley Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King’s College London. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care. The EU-GEI Project is funded by the European Community’s Seventh Framework Programme under grant agreement No. HEALTH-F2-…

Unraveling the relationship of loneliness and isolation in schizophrenia: Polygenic dissection and causal inference

ABSTRACTThere is increasing recognition of the association between loneliness and social isolation (LNL-ISO) with schizophrenia. Here, we demonstrate significant LNL-ISO polygenic score prediction on schizophrenia in an independent case-control sample (N=3,488). We then dissect schizophrenia predisposing variation into subsets of variants based on their effect on LNL-ISO. Genetic variation with concordant effects in both phenotypes show significant SNP-based heritability enrichment, higher polygenic predictive ability in females and positive covariance with other mental disorders such as depression, anxiety, attention-deficit hyperactivity, alcohol use disorder, and autism. Conversely, gene…