Recent progress in the genomics and epigenomics of addiction has contributed to improving our understanding of this complex mental disorder's etiology, filling the gap between genes, environment, and behavior. We review the behavioral genetic studies reporting gene and environment interactions that explain the polygenetic contribution to the resilience and vulnerability to develop addiction. We discuss

Recent genetic progress allows the molecular diagnosis of young‐onset dementia, including Alzheimer's disease (AD) and frontotemporal dementia (FTD). We aimed to identify the mutational and clinical spectra of causal genes in a Taiwanese cohort of young‐onset dementia. Ninety‐one patients with young‐onset dementia and 22 age/gender‐matched controls were recruited. Genetic causes were identified by

HeiDE is a longitudinal population‐based study that started in the 1990s and, at baseline, assessed an array of health‐related personality questionnaires in 5133 individuals. Five latent personality dimensions (The Heidelberg Five) were identified and interpreted as Emotional Lability (ELAB), Lack of Behavioral Control (LBCN), Type A Behavior (TYAB), Locus of Control over Disease (LOCC), and Psychoticism

Philipp Jolly's 1913 extensive monograph “The Heredity of Psychoses” provides, in both his detailed literature review and new pedigree study, an extensive assessment of a key issue in the psychiatric genetics of his day: the degree to which the familial transmission of psychiatric disorders was specific (or homogeneous) versus nonspecific (or heterogeneous). Contrary to a number of earlier observations

This study analyzed gene expression messenger RNA data, from cases with major depressive disorder (MDD) and controls, using supervised machine learning (ML). We built on the methodology of prior studies to obtain more generalizable/reproducible results. First, we obtained a classifier trained on gene expression data from the dorsolateral prefrontal cortex of post‐mortem MDD cases (n = 126) and controls

Sleep is essential to the human brain and is regulated by genetics with many features conserved across species. Sleep is also influenced by health and environmental factors; identifying replicable genetic variants contributing to sleep may require accounting for these factors. We examined how stress and mood disorder contribute to sleep and impact its heritability. Our sample included 326 Amish/Mennonite

Variants identified by genome‐wide association studies (GWAS) are often expression quantitative trait loci (eQTLs), suggesting they are proxies or are themselves regulatory. Across many data sets, analyses show that variants often affect multiple genes. Lacking data on many tissue types, developmental time points, and homogeneous cell types, the extent of this one‐to‐many relationship is underestimated

Genotype imputation across populations of mixed ancestry is critical for optimal discovery in large‐scale genome‐wide association studies (GWAS). Methods for direct imputation of GWAS summary‐statistics were previously shown to be practically as accurate as summary statistics produced after raw genotype imputation, while incurring orders of magnitude lower computational burden. Given that direct imputation

Schizophrenia is a severe mental disease characterized with positive symptoms, negative symptoms, and cognitive impairments. Although recent genome‐wide association studies (GWASs) have identified over 145 risk loci for schizophrenia, pinpointing the causal variants and genes at the reported loci and elucidating their roles in schizophrenia remain major challenges. Here we identify a functional single‐nucleotide

Between April 20, 2020 and June 19, 2020 we conducted a survey of the membership of the Psychiatric Genomics Consortium (PGC) to explore the impact of COVID‐19 on their research and academic careers. A total of 123 individuals responded representing academic ranks from trainee to full professor, tenured and fixed‐term appointments, and all genders. The survey included both quantitative and free text

After decades of methodological stasis in 19th century psychiatric genetics, when uncontrolled studies reported high rates of hereditary burden in hospitalized patients, Koller completed the first controlled study in 1895. We pick up this narrative 7 years later when the well‐known Julius Wagner v. Jauregg published a biting critique of the then current psychiatric genetics' literature. In 1905, partially

Treatment strategies for alcohol use disorder (AUD) aim for abstinence or harm reduction. While deranged biochemical parameters reverse with alcohol abstinence, whether molecular changes at the epigenetic level reverse is not clearly understood. We investigated whether the reduction from high alcohol use reflects DNA methylation at the gene‐specific and global level. In subjects seeking treatment for

Patients with substance use disorders (SUD) are at high risk to die by suicide. So far, the neurobiology of the suicide‐SUD association has not been elucidated. This study aimed to identify potential pharmacological targets among hub genes from brain gene co‐expression networks of individuals with SUD in a suicidal and non‐suicidal context. Post‐mortem samples from the prefrontal cortex of 79 individuals

Genome‐wide association studies have identified multiple genetic risk factors underlying susceptibility to substance use, however, the functional genes and biological mechanisms remain poorly understood. The discovery and characterization of risk genes can be facilitated by the integration of genome‐wide association data and gene expression data across biologically relevant tissues and/or cell types

Attention‐deficit/hyperactivity disorder (ADHD) symptoms are continuously distributed in the general population, where both genetic and environmental factors play roles. Stressful life events (SLEs) have been associated with ADHD diagnosis, but the relationship between ADHD genetic liability, SLEs, and ADHD symptoms in healthy individuals is less clear. Using a sample of 1,531 healthy adults (average

Substance use disorder (SUD) often co‐occur at high prevalence with other psychiatric conditions. Among them, attention‐deficit and hyperactivity disorder (ADHD) is present in almost one out of every four subjects with SUD and is associated with higher severity, more frequent polysubstance dependence and increased risk for other mental health problems in SUD patients. Despite studies suggesting a genetic

Multiple genome‐wide association studies of schizophrenia have reported associations between genetic variants within the MHC region and disease risk, an association that has been partially accounted for by alleles of the complement component 4 (C4) gene. Following on previous findings of association between both C4 and other complement‐related variants and memory function, we tested the hypothesis

Genetic signal detection in genome‐wide association studies (GWAS) is enhanced by pooling small signals from multiple Single Nucleotide Polymorphism (SNP), for example, across genes and pathways. Because genes are believed to influence traits via gene expression, it is of interest to combine information from expression Quantitative Trait Loci (eQTLs) in a gene or genes in the same pathway. Such methods

Twin studies indicate that there is a significant genetic contribution to the risk of developing alcohol use disorder (AUD). With the exception of coding variants in ADH1B and ALDH2, little is known about the molecular effects of AUD‐associated loci. We previously reported that the AUD‐associated synonymous polymorphism rs279858 within the GABAA α2 receptor subunit gene, GABRA2, was associated with

Associations between adult attention‐deficit/hyperactivity disorder (ADHD) symptoms and dietary habits have not been well established and the underlying mechanisms remain unclear. We explored these associations using a Swedish population‐based twin study with 17,999 individuals aged 20–47 years. We estimated correlations between inattention and hyperactivity/impulsivity with dietary habits and fitted

Neurodevelopmental disorders, including autism spectrum disorder (ASD), intellectual disability (ID), developmental disorders (DD) and epileptic encephalopathy (EE), have a strong clinical comorbidity, which indicates a common genetic etiology across various disorders. However, the underlying genetic mechanisms of comorbidity and specificity remain unknown across neurodevelopmental disorders. Based

Schizophrenia has substantial variation in symptom severity, course of illness, and overall functioning. Earlier age of onset (AOO) is consistently associated with negative outcomes and yet the causes of this association are still unknown. We used a multiplex, extended pedigree design (total N = 771; 636 relatives from 43 multigenerational families with at least 2 relatives diagnosed with schizophrenia

STXBP1, also known as Munc‐18, is a master regulator of neurotransmitter release and synaptic function in the human brain through its direct interaction with syntaxin 1A. STXBP1 binds syntaxin 1A is an inactive conformational state. STXBP1 decreases its binding affinity to syntaxin upon phosphorylation, enabling syntaxin 1A to engage in the SNARE complex, leading to neurotransmitter release. STXBP1‐related

Genome‐wide association studies are rapidly advancing our understanding of the genetic architecture of complex disorders, including many psychiatric conditions such as major depression, schizophrenia, and substance use disorders. One common goal of genome‐wide association studies is to use findings for enhanced clinical prediction in the future, which can aid in identifying at‐risk individuals to enable

Throughout the 19th century, many alienists reported the proportion of their patients who were “hereditarily burdened,” meaning they had a positive family history for mental illness. The rates of such burden differed widely because different authors used divergent definition of illness and investigated different groups of relatives. Most importantly, no authors compared rates of burden with those seen

People with attention‐deficit/hyperactivity disorder (ADHD) or other psychiatric disorders show high rates of nicotine dependence (ND). This comorbidity might be (partly) explained by shared genetic factors. Genetic correlations between ND and ADHD (or other psychiatric disorders) have not yet been estimated. A significant genetic correlation might indicate genetic overlap, but could also reflect a

This study investigated the genetic components of ADHD and ASD by examining the cross‐disorder trait of emotion recognition problems. The genetic burden for ADHD and ASD on previously identified emotion recognition factors (speed and accuracy of visual and auditory emotion recognition) and classes (Class 1: Average visual, impulsive auditory; Class 2: Average‐strong visual & auditory; Class 3: Impulsive

Cannabis use is highly prevalent and is associated with adverse and beneficial effects. To better understand the full spectrum of health consequences, biomarkers that accurately classify cannabis use are needed. DNA methylation (DNAm) is an excellent candidate, yet no blood‐based epigenome‐wide association studies (EWAS) in humans exist. We conducted an EWAS of lifetime cannabis use (ever vs. never)

It is imperative to understand the specific and shared etiologies of major depression and cardio‐metabolic disease, as both traits are frequently comorbid and each represents a major burden to society. This study examined whether there is a genetic association between major depression and cardio‐metabolic traits and if this association is stratified by age at onset for major depression. Polygenic risk

Autism (or autism spectrum disorder [ASD]) is an often disabling childhood neurologic condition of mostly unknown cause. We previously explored whether there was an association of ASD with any analyte measured in the first newborn screening blood test. Here we explore the second screen. Our matched case–control study examined data on 3–5 year‐old patients with any ASD diagnosis in the Texas Medicaid

The Huntingtin (HTT ) gene contains a CAG repeat in exon 1, whose expansion beyond 39 repeats consistently leads to Huntington's disease (HD), whereas normal‐to‐intermediate alleles seemingly modulate brain structure, function and behavior. The role of the CAG repeat in Autism Spectrum Disorder (ASD) was investigated applying both family‐based and case–control association designs, with the SCA3 repeat

Characteristics of Huntington's disease (HD) differ among various ethnicities. Few studies have explored the relationship between phenotypes and genotypes of HD in Asians. We evaluated the relationship between integrated clinical and imaging phenotypes and genotypes in a Taiwanese HD cohort, enrolling 123 HD patients genetically diagnosed between August 1994 and February 2019. The clinical presentations

Schizophrenia shows a genetic correlation with both anxiety disorder and neuroticism, a trait strongly associated with anxiety. However, genetic correlations do not discern causality from genetic confounding. We therefore aimed to investigate whether anxiety‐related phenotypes lie on the causal pathway to schizophrenia using Mendelian randomization (MR). Four MR methods, each with different assumptions

While abnormal neurodevelopment contributes to schizophrenia (SCZ) risk, there is also evidence to support a role for immune dysfunction in SCZ. BCL11B , associated with SCZ in genome‐wide association study (GWAS), is a transcription factor that regulates the differentiation and development of cells in the central nervous and immune systems. Here, we use functional genomics data from studies of BCL11B

The 22q11.2 deletion syndrome (22q11DS) is associated with impaired cognitive functions and increased risk for schizophrenia spectrum disorders. Speech and language deficits are prominent, with evidence of decline anteceding emergence of psychosis. There is paucity of data examining language function in children with 22q11DS with follow‐up assessment of psychosis spectrum (PS) symptoms. We examined

Expressive language impairment is one of the most frequently associated clinical features of 16p11.2 copy number variations (CNV). However, our understanding of the language profiles of individuals with 16p11.2 CNVs is still limited. This study builds upon previous work in the Simons Variation in Individuals Project (VIP, now known as Simons Searchlight), to characterize language abilities in 16p11

African Americans (AA) have lower prevalence of alcohol dependence and higher subjective response to alcohol than European Americans. Genome‐wide association studies (GWAS) have identified genes/variants associated with alcohol dependence specifically in AA; however, the sample sizes are still not large enough to detect variants with small effects. Admixture mapping is an alternative way to identify

Variations in SLC9A9 gene expression and protein function are associated with multiple human diseases, which range from Attention‐deficit/hyperactivity disorder (ADHD) to glioblastoma multiforme. In an effort to determine the full spectrum of human disease associations with SLC9A9 , we performed a systematic review of the literature. We also review SLC9A9's biochemistry, protein structure, and function

Autism spectrum disorder (ASD) is a relatively common childhood onset neurodevelopmental disorder with a complex genetic etiology. While progress has been made in identifying the de novo mutational landscape of ASD, the genetic factors that underpin the ASD's tendency to run in families are not well understood. In this study, nine extended pedigrees each with three or more individuals with ASD, and

The aim of this systematic review was to synthesize the existing evidence documenting the psychosocial implications of living with a familial risk of an adult‐onset psychiatric disorder. Six databases were searched systematically to identify qualitative and quantitative studies, which explored perspectives of those at increased risk for psychiatric disorders, as well as the general public. Thematic

It is unclear to what extent parental influences on the development of internalizing problems in offspring are explained by indirect genetic effects, reflected in the environment provided by the parent, in addition to the genes transmitted from parent to child. In this study, these effects were investigated using two innovative methods in a large birth cohort. Using maternal‐effects genome complex

Evidence from family and twin studies points to a genetic contribution to the etiology of eating disorders (EDs), confirmed by the association of several single nucleotide polymorphisms (SNPs) with this group of disorders. Previous reports have suggested that the serotonin receptor (5-HT2AR) and brain-derived neurotrophic factor (BDNF) genes could be both involved in EDs susceptibility. In order to

WBP1L is a target of microRNA 137 (miR‐137) and has been considered a candidate gene for schizophrenia (SCZ). To investigate the relationships between WBP1L and SCZ and its related symptom scales, a total of 5,993 Chinese Han subjects, including 2,128 SCZ patients and 3,865 controls, were enrolled. In addition, an independent sample set for replication study including 1,052 SCZ patients and 2,124 controls

Hearing loss (HL) is the most common sensory disorder worldwide and genetic factors contribute to approximately half of congenital HL cases. HL is subject to extensive genetic heterogeneity, rendering molecular diagnosis difficult. Mutations of the transmembrane channel‐like 1 (TMC1) gene cause hearing defects in humans and mice. The precise function of TMC1 protein in the inner ear is unknown, although

Cognitive impairment is a frequent and serious problem in patients with various forms of severe mental illnesses (SMI), including schizophrenia (SZ) and bipolar disorder (BP). Recent research suggests genetic links to several cognitive phenotypes in both SMI and in the general population. Our goal in this study was to identify potential genomic signatures of cognitive functioning in veterans with severe

Variations in MYT1L, a gene encoding a transcription factor expressed in the brain, have been associated with autism, intellectual disability, and schizophrenia. Here we provide an updated review of published reports of neuropsychiatric correlates of loss of function and duplication of MYT1L. Of 27 duplications all were partial; 33% were associated exclusively with schizophrenia, and the chromosomal

Individuals with attention deficit hyperactivity disorder (ADHD) show gray matter volume (GMV) reduction in the putamen. KTN1 variants may regulate kinectin 1 expression in the putamen and influence putamen structure and function. We aim to test the hypothesis that the KTN1 variants may represent a genetic risk factor of ADHD. Two independent family-based Caucasian samples were analyzed, including

Chromosome 15q24 microdeletion syndrome is characterized by developmental delay, facial dysmorphism, hearing loss, hypotonia, recurrent infection, and other congenital malformations including microcephaly, scoliosis, joint laxity, digital anomalies, as well as sometimes having autism spectrum disorder (ASD) and attention deficit hyperactivity disorder. Here, we report a boy with a 2.58-Mb de novo deletion

We investigated whether obsessive-compulsive (OC) symptoms from a population-based sample could be analyzed to detect genetic variants influencing obsessive-compulsive disorder (OCD). We performed a genome-wide association studies (GWAS) on the obsession (rumination and impulsions) and compulsion (checking, washing, and ordering/precision) subscales of an abbreviated version of the Padua Inventory

Anxiety disorders (ANX), namely generalized anxiety, panic disorder, and phobias, are common, etiologically complex syndromes that show increasing prevalence and comorbidity throughout adolescence and beyond. Few genome-wide association studies (GWAS) examining ANX risk have been published and almost exclusively in individuals of European ancestry. In this study, we phenotyped participants from the

Schizophrenia is a complex and chronic neuropsychiatric disorder, with a heritability of around 60-80%. Large (>100 kb) rare (<1%) copy number variants (CNVs) occur more frequently in schizophrenia patients compared to controls. Currently, there are no studies reporting genome-wide CNVs in clinical high risk for psychosis (CHR-P) individuals. The aim of this study was to investigate the role of rare

Schizophrenia (SZ) onset and treatment outcome have important genetic components, however individual genes do not have strong effects on SZ phenotype. Therefore, it is important to use the pathway-based approach and study metabolic and signaling pathways, such as dopaminergic and serotonergic. Serotonin pathway has an important role in brain signaling, nevertheless, its role in SZ is not as thoroughly

Hereditary tyrosinemia Type 1 (HT-1) is a rare metabolic disease where the enzyme catalyzing the final step of tyrosine breakdown is defect, leading to accumulation of toxic metabolites. Nitisinone inhibits the degradation of tyrosine and thereby the production of harmful metabolites, however, the concentration of tyrosine also increases. We investigated the relationship between plasma tyrosine concentrations

Decreased insular volume may be one of the anatomical alterations caused by schizophrenia. The possibility of region-specific insular volumetric reduction as an endophenotype and/or a possible treatment predictor is a critical issue with great implications for the diagnosis and prognosis of the disease. The sample of the current study comprised 44 drug-naive and first-episode patients, 42 unaffected