Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 12.947
Filtrar
1.
Yi Chuan ; 41(8): 677-685, 2019 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-31447419

RESUMO

MicroRNAs (miRNAs) compose a class of non-coding transcripts with a mean length of 22 nucleotides, and play critical roles in regulating gene expression in the process of development, proliferation and differentiation of neurons. Recent genome-wide association studies (GWAS) find most of schizophrenia-associated single nucleotide polymorphisms (SNPs) locating in the non-coding regions, providing functional implications of miRNAs in the development of schizophrenia. In this review, we highlight the interplays between GWAS-SNPs and miRNAs in four perspectives: SNP in miRNA gene; miRNA located in the host gene; SNP located in the miRNA's seed sequence; SNP located in the miRNA's binding site. We also speculate on the future research on the role of miRNA in the development of schizophrenia.


Assuntos
MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Esquizofrenia/genética , Sítios de Ligação , Estudo de Associação Genômica Ampla , Humanos
2.
Adv Exp Med Biol ; 1121: 7-20, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31392648

RESUMO

Common Non communicable diseases (NCDs), such as cardiovascular disease, cancer, schizophrenia, and diabetes, have become the major cause of death in the world. They result from an interaction between genetics, lifestyle and environmental factors. The prevalence of NCDs are increasing, and researchers hopes to find efficient strategies to predict, prevent and treat them. Given the role of epigenome in the etiology of NCDs, insight into epigenetic mechanisms may offer opportunities to predict, detect, and prevent disease long before its clinical onset.Epigenetic alterations are exerted through several mechanisms including: chromatin modification, DNA methylation and controlling gene expression by non-coding RNAs (ncRNAs). In this chapter, we will discuss about NCDs, with focus on cancer, diabetes and schizophrenia. Different epigenetic mechanisms, categorized into two main groups DNA methylation and chromatin modifications and non-coding RNAs, will be separately discussed for these NCDs.


Assuntos
Epigênese Genética , Doenças não Transmissíveis , Metilação de DNA , Diabetes Mellitus Tipo 2/genética , Humanos , Neoplasias/genética , Esquizofrenia/genética
3.
Genome Biol ; 20(1): 135, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288836

RESUMO

BACKGROUND: The importance of cell type-specific epigenetic variation of non-coding regions in neuropsychiatric disorders is increasingly appreciated, yet data from disease brains are conspicuously lacking. We generate cell type-specific whole-genome methylomes (N = 95) and transcriptomes (N = 89) from neurons and oligodendrocytes obtained from brain tissue of patients with schizophrenia and matched controls. RESULTS: The methylomes of the two cell types are highly distinct, with the majority of differential DNA methylation occurring in non-coding regions. DNA methylation differences between cases and controls are subtle compared to cell type differences, yet robust against permuted data and validated in targeted deep-sequencing analyses. Differential DNA methylation between control and schizophrenia tends to occur in cell type differentially methylated sites, highlighting the significance of cell type-specific epigenetic dysregulation in a complex neuropsychiatric disorder. CONCLUSIONS: Our results provide novel and comprehensive methylome and transcriptome data from distinct cell populations within patient-derived brain tissues. This data clearly demonstrate that cell type epigenetic-differentiated sites are preferentially targeted by disease-associated epigenetic dysregulation. We further show reduced cell type epigenetic distinction in schizophrenia.


Assuntos
Encéfalo/metabolismo , Metilação de DNA , Epigênese Genética , Esquizofrenia/genética , Encéfalo/citologia , Estudos de Casos e Controles , Humanos , Esquizofrenia/metabolismo
4.
Nat Commun ; 10(1): 2417, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160569

RESUMO

Accumulating evidence from genome wide association studies (GWAS) suggests an abundance of shared genetic influences among complex human traits and disorders, such as mental disorders. Here we introduce a statistical tool, MiXeR, which quantifies polygenic overlap irrespective of genetic correlation, using GWAS summary statistics. MiXeR results are presented as a Venn diagram of unique and shared polygenic components across traits. At 90% of SNP-heritability explained for each phenotype, MiXeR estimates that 8.3 K variants causally influence schizophrenia and 6.4 K influence bipolar disorder. Among these variants, 6.2 K are shared between the disorders, which have a high genetic correlation. Further, MiXeR uncovers polygenic overlap between schizophrenia and educational attainment. Despite a genetic correlation close to zero, the phenotypes share 8.3 K causal variants, while 2.5 K additional variants influence only educational attainment. By considering the polygenicity, discoverability and heritability of complex phenotypes, MiXeR analysis may improve our understanding of cross-trait genetic architectures.


Assuntos
Transtorno Bipolar/genética , Modelos Genéticos , Modelos Estatísticos , Herança Multifatorial , Esquizofrenia/genética , Frequência do Gene , Estudo de Associação Genômica Ampla , Humanos , Desequilíbrio de Ligação
5.
BMC Bioinformatics ; 20(Suppl 12): 313, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31216978

RESUMO

BACKGROUND: Schizophrenia and autism are examples of polygenic diseases caused by a multitude of genetic variants, many of which are still poorly understood. Recently, both diseases have been associated with disrupted neuron motility and migration patterns, suggesting that aberrant cell motility is a phenotype for these neurological diseases. RESULTS: We formulate the POLYGENIC DISEASE PHENOTYPE Problem which seeks to identify candidate disease genes that may be associated with a phenotype such as cell motility. We present a machine learning approach to solve this problem for schizophrenia and autism genes within a brain-specific functional interaction network. Our method outperforms peer semi-supervised learning approaches, achieving better cross-validation accuracy across different sets of gold-standard positives. We identify top candidates for both schizophrenia and autism, and select six genes labeled as schizophrenia positives that are predicted to be associated with cell motility for follow-up experiments. CONCLUSIONS: Candidate genes predicted by our method suggest testable hypotheses about these genes’ role in cell motility regulation, offering a framework for generating predictions for experimental validation.


Assuntos
Movimento Celular/genética , Doença/genética , Redes Reguladoras de Genes , Herança Multifatorial/genética , Algoritmos , Transtorno Autístico/genética , Estudos de Associação Genética , Humanos , Aprendizado de Máquina , Fenótipo , Curva ROC , Reprodutibilidade dos Testes , Esquizofrenia/genética
6.
Nat Neurosci ; 22(7): 1066-1074, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31209380

RESUMO

Cannabis is the most frequently used illicit psychoactive substance worldwide; around one in ten users become dependent. The risk for cannabis use disorder (CUD) has a strong genetic component, with twin heritability estimates ranging from 51 to 70%. Here we performed a genome-wide association study of CUD in 2,387 cases and 48,985 controls, followed by replication in 5,501 cases and 301,041 controls. We report a genome-wide significant risk locus for CUD (P = 9.31 × 10-12) that replicates in an independent population (Preplication = 3.27 × 10-3, Pmeta-analysis = 9.09 × 10-12). The index variant (rs56372821) is a strong expression quantitative trait locus for cholinergic receptor nicotinic α2 subunit (CHRNA2); analyses of the genetically regulated gene expression identified a significant association of CHRNA2 expression with CUD in brain tissue. At the polygenic level, analyses revealed a significant decrease in the risk of CUD with increased load of variants associated with cognitive performance. The results provide biological insights and inform on the genetic architecture of CUD.


Assuntos
Abuso de Maconha/genética , Proteínas do Tecido Nervoso/fisiologia , Receptores Nicotínicos/fisiologia , Idade de Início , Alelos , Transtorno do Deficit de Atenção com Hiperatividade/genética , Encéfalo/metabolismo , Estudos de Casos e Controles , Cromossomos Humanos Par 8/genética , Cognição/fisiologia , Estudos de Coortes , Fatores de Confusão (Epidemiologia) , Dinamarca , Escolaridade , Feminino , Perfilação da Expressão Gênica , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Islândia , Masculino , Herança Multifatorial , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Receptores Nicotínicos/biossíntese , Receptores Nicotínicos/genética , Esquizofrenia/genética , Fumar/genética , Transcriptoma
7.
Nat Commun ; 10(1): 2046, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-31053723

RESUMO

Impaired neuronal processes, including dopamine imbalance, are central to the pathogenesis of major psychosis, but the molecular origins are unclear. Here we perform a multi-omics study of neurons isolated from the prefrontal cortex in schizophrenia and bipolar disorder (n = 55 cases and 27 controls). DNA methylation, transcriptomic, and genetic-epigenetic interactions in major psychosis converged on pathways of neurodevelopment, synaptic activity, and immune functions. We observe prominent hypomethylation of an enhancer within the insulin-like growth factor 2 (IGF2) gene in major psychosis neurons. Chromatin conformation analysis revealed that this enhancer targets the nearby tyrosine hydroxylase (TH) gene responsible for dopamine synthesis. In patients, we find hypomethylation of the IGF2 enhancer is associated with increased TH protein levels. In mice, Igf2 enhancer deletion disrupts the levels of TH protein and striatal dopamine, and induces transcriptional and proteomic abnormalities affecting neuronal structure and signaling. Our data suggests that epigenetic activation of the enhancer at IGF2 may enhance dopamine synthesis associated with major psychosis.


Assuntos
Transtorno Bipolar/genética , Dopamina/biossíntese , Elementos Facilitadores Genéticos/genética , Epigênese Genética , Fator de Crescimento Insulin-Like II/genética , Esquizofrenia/genética , Tirosina 3-Mono-Oxigenase/genética , Adulto , Idoso , Animais , Transtorno Bipolar/patologia , Metilação de DNA , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Neurônios/patologia , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/patologia , Proteômica , Esquizofrenia/patologia , Transcriptoma/genética , Tirosina 3-Mono-Oxigenase/metabolismo , Adulto Jovem
8.
Artigo em Russo | MEDLINE | ID: mdl-31089096

RESUMO

AIM: To search for genetic variants associated with premorbid personality in patients with schizophrenia. MATERIAL AND METHODS: The sample included 272 men diagnosed with schizophrenia or schizoaffective disorder. Patients were divided into 3 groups based on premorbid personality difficulties: mild (group 1, n=110), moderate (group 2, n=113), marked (group 3, n=49). The following polymorphisms were genotyped: 5-HTR2A (T102C), 5-HTTLPR, BDNF (Val66Met), CRP (-717A>G). RESULTS: A significant increase in the frequency of the CC (5-HTR2A T102C), LL (5-HTTLPR) and Met/Met (BDNF Val66Met) genotypes was identified in group 3 compared to group 1. Frequencies of CC and LL genotypes were significantly higher in group 2 compared to group 1 as well. The differences between group 2 and group 3 were found only for the Met/Met genotype. There were no between-group differences in the frequencies of CRP (-717A>G) genotypes. CONCLUSION: 5-HTR2A (T102C), 5-HTTLPR, BDNF (Val66Met) polymorphisms previously reported to modify schizophrenia course are also associated with premorbid personality in schizophrenic patients.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Serina Peptidase 2 de Requerimento de Alta Temperatura A , Personalidade , Transtornos Psicóticos , Esquizofrenia , Proteínas da Membrana Plasmática de Transporte de Serotonina , Fator Neurotrófico Derivado do Encéfalo/genética , Genótipo , Serina Peptidase 2 de Requerimento de Alta Temperatura A/genética , Humanos , Masculino , Personalidade/genética , Polimorfismo Genético , Receptor 5-HT2A de Serotonina , Esquizofrenia/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética
9.
Nat Genet ; 51(5): 793-803, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31043756

RESUMO

Bipolar disorder is a highly heritable psychiatric disorder. We performed a genome-wide association study (GWAS) including 20,352 cases and 31,358 controls of European descent, with follow-up analysis of 822 variants with P < 1 × 10-4 in an additional 9,412 cases and 137,760 controls. Eight of the 19 variants that were genome-wide significant (P < 5 × 10-8) in the discovery GWAS were not genome-wide significant in the combined analysis, consistent with small effect sizes and limited power but also with genetic heterogeneity. In the combined analysis, 30 loci were genome-wide significant, including 20 newly identified loci. The significant loci contain genes encoding ion channels, neurotransmitter transporters and synaptic components. Pathway analysis revealed nine significantly enriched gene sets, including regulation of insulin secretion and endocannabinoid signaling. Bipolar I disorder is strongly genetically correlated with schizophrenia, driven by psychosis, whereas bipolar II disorder is more strongly correlated with major depressive disorder. These findings address key clinical questions and provide potential biological mechanisms for bipolar disorder.


Assuntos
Transtorno Bipolar/genética , Loci Gênicos , Transtorno Bipolar/classificação , Estudos de Casos e Controles , Transtorno Depressivo Maior/genética , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Transtornos Psicóticos/genética , Esquizofrenia/genética , Biologia de Sistemas
10.
Proc Jpn Acad Ser B Phys Biol Sci ; 95(5): 179-197, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31080187

RESUMO

The adult human brain consists of approximately a hundred billion neurons, which are connected via synapses. The pattern and strength of the synaptic connections are constantly changing (synaptic plasticity), and these changes are considered to underlie learning, memory, and personality. Many psychiatric disorders have been related to disturbances in synaptogenesis and subsequent plasticity. In this review, we summarize findings of synaptic disturbance and its involvement in the pathogenesis and/or pathophysiology of psychiatric disorders. We will focus on schizophrenia, because this condition has a high proven heritability, which offers more unambiguous insights into the biological origins of not only schizophrenia but also related psychiatric disorders. To demonstrate the involvement of synaptopathy in psychiatric disorders, we discuss what knowledge is missing at the circuits level, and what new technologies are needed to achieve a comprehensive understanding of synaptopathy in psychiatric disorders.


Assuntos
Esquizofrenia/genética , Esquizofrenia/patologia , Sinapses/patologia , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Humanos , Optogenética , Esquizofrenia/diagnóstico por imagem
11.
Dis Markers ; 2019: 8062397, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31061683

RESUMO

Recent research has shown that prenatal famine exposure may be one of the risk factors for schizophrenia and that people born in famine years may be at an increased risk of schizophrenia due to alteration of the DNA methylation of genes. In this study, the association of rs2283291/rs4648635 and the incidence of schizophrenia and prenatal famine exposure at the genetic level were investigated to provide clues to the pathogenesis of schizophrenia. A total of 960 participants were recruited, comprising 473 prenatal famine-exposed individuals (225 patients and 248 controls) and 487 prenatal non-famine-exposed individuals (220 patients and 267 controls). The association of prenatal famine, schizophrenia, and their interaction with DNA methylation levels was analyzed using SPSS and GMDR software. Gender stratification analysis revealed a significant association between the rs2283291 genotype and schizophrenia in male patients (P = 0.017), and difference still existed after correction by the Bonferroni method. It was also found that an increasing risk of schizophrenia was associated with rs2283291 in males (OR: 1.62, 95% CI: 1.13-2.33, P = 0.0086, AIC = 669.7) in an overdominant model. The results of gene-environment interaction and gene-gene interaction revealed no association with the risk of schizophrenia. This study reported for the first time that rs2283291 was associated with schizophrenia in Chinese males.


Assuntos
Canais de Cálcio Tipo L/genética , Desnutrição/epidemiologia , Polimorfismo de Nucleotídeo Único , Esquizofrenia/genética , China , Feminino , Interação Gene-Ambiente , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/epidemiologia , Fatores Sexuais
12.
Nat Neurosci ; 22(5): 691-699, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30988527

RESUMO

Genome-wide association studies (GWAS) have identified more than 100 schizophrenia (SCZ)-associated loci, but using these findings to illuminate disease biology remains a challenge. Here we present integrative risk gene selector (iRIGS), a Bayesian framework that integrates multi-omics data and gene networks to infer risk genes in GWAS loci. By applying iRIGS to SCZ GWAS data, we predicted a set of high-confidence risk genes, most of which are not the nearest genes to the GWAS index variants. High-confidence risk genes account for a significantly enriched heritability, as estimated by stratified linkage disequilibrium score regression. Moreover, high-confidence risk genes are predominantly expressed in brain tissues, especially prenatally, and are enriched for targets of approved drugs, suggesting opportunities to reposition existing drugs for SCZ. Thus, iRIGS can leverage accumulating functional genomics and GWAS data to advance our understanding of SCZ etiology and potential therapeutics.


Assuntos
Redes Reguladoras de Genes , Predisposição Genética para Doença , Genômica/métodos , Esquizofrenia/genética , Animais , Teorema de Bayes , Modelos Animais de Doenças , Estudo de Associação Genômica Ampla , Humanos , Camundongos , Fatores de Risco
14.
J Genet ; 982019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30945684

RESUMO

Microduplications of the X chromosome are a rare cause of X-linked intellectual disability (XLID), a clinically and genetically heterogeneous spectrum of disorders. In the present study, a 950-kb Xp22.12 microduplication including the RPS6KA3 gene was detected in affected members of a family, including the proband (male), his mother and one maternal uncle. Four female carriers had major depression and one of them also had mild intellectual disability. The present and previous cases with overlapping microduplications suggest that Xp22.12 microduplications can be included in the neuropsychiatric copy number variations.


Assuntos
Cromossomos Humanos X/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Deficiência Intelectual/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Esquizofrenia/genética , Adulto , Duplicação Cromossômica , Variações do Número de Cópias de DNA , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Humanos , Deficiência Intelectual/diagnóstico , Masculino , Pessoa de Meia-Idade , Linhagem , Esquizofrenia/diagnóstico
15.
Clin Lab ; 65(4)2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30969072

RESUMO

BACKGROUND: Schizophrenia (SCZ) is a serious mental disorder that interferes with a person's cognitive processes and leads to social disability. A wide range of factors may play important roles in increased risk of SCZ development. Genetic contributors are among the most influential actors involved in different molecular mechanisms leading to the development of the nervous system, thus they play pivotal roles in psychotic disorders and SCZ de-velopment. RAB8B is characterized for its key roles in several cellular and molecular mechanisms which are linked with different psychotic disorders, such as SCZ. METHODS: In this study, we assessed the expression level of RAB8B gene in blood samples of schizophrenic patients and normal healthy controls by means of quantitative real time PCR. We also investigated the correlation between RAB8B-rs1986112 genotypes and RAB8B expression levels through SNP genotyping by means of the PCR-RFLP method. RESULTS: Our results indicated a significant difference of RAB8B mRNA ratio between SCZ patients and healthy controls. Moreover, we showed significant upregulation of RAB8B in patients with rs1986112 GG and AG genotype compared to AA genotype. CONCLUSIONS: Our findings suggest a role for RAB8B and its regulatory variation, rs1986112 in SCZ development.


Assuntos
Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Polimorfismo de Nucleotídeo Único , Esquizofrenia/genética , Adulto , Estudos de Casos e Controles , Cognição , Biologia Computacional , Primers do DNA/genética , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Reação em Cadeia da Polimerase em Tempo Real , Risco , Regulação para Cima
16.
Nord J Psychiatry ; 73(2): 90-95, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30900499

RESUMO

BACKGROUND: Genetic studies have provided convergent results indicating that schizophrenia is a polygenic disorder with a heritability estimate of ∼60-80%. The propensity for schizophrenia is ∼10 times higher in individuals with first-degree relatives with schizophrenia when compared to the general population. AIM: To identify associations between parental characteristics and the risk of schizophrenia in a Chinese population. METHODS: Participants with a diagnosis of schizophrenia were recruited along with healthy controls (HCs) matched for age and gender from Weifang, China. Logistic regression models and generalized linear models were used to explore the associations between parental characteristics with the risk and age at onset of schizophrenia. In total, 414 cases and 639 HCs were recruited for the study. RESULTS: We observed an inverse association between levels of paternal and maternal education and risk of schizophrenia after controlling for potential confounders (Paternal: OR = 1.525, 95% CI: 1.080-2.153, p = .017; Maternal: OR = 1.984, 95% CI: 1.346-2.924, p = .001). Younger paternal and maternal childbearing age were associated with a higher risk of diagnosis of schizophrenia. We furtherly observed that individuals with earlier age at onset of schizophrenia had fewer siblings (p = .007) and had higher rates of parental marital disharmony (p = .033). CONCLUSION: Our results indicate that parental years of education and age of childbearing are associated with an increased risk of schizophrenia in a Chinese population. Age of onset of schizophrenia was positively associated with a greater number of siblings and negatively associated with parental marital disharmony.


Assuntos
Escolaridade , Idade Materna , Pais/psicologia , Idade Paterna , Esquizofrenia/epidemiologia , Psicologia do Esquizofrênico , Adulto , Idade de Início , Estudos de Casos e Controles , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População/métodos , Fatores de Risco , Esquizofrenia/diagnóstico , Esquizofrenia/genética , Irmãos/psicologia
17.
Psychiatry Res ; 274: 391-394, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30901624

RESUMO

We investigated the role of DGCR2, a corticogenesis-related gene, on schizophrenia (SZ) and its subphenotypes, including brain morphology. A total of 221 SZ patients, 263 controls and 70 antipsychotic-naïve first episode of psychosis (FEP) were genotyped for 17 DGCR2 polymorphisms. While no association between DGCR2 polymorphisms and SZ was found, the missense variant rs2072123 was associated to left rostral anterior cingulate thickness, showing that DGCR2 seems not to be associated directly with the SZ but might be influencing the brain morphology. We also showed a DGCR2 downregulation in SZ patients when compared to controls and FEP.


Assuntos
Giro do Cíngulo/patologia , Complexo Glicoproteico GPIb-IX de Plaquetas/genética , Esquizofrenia/genética , Esquizofrenia/patologia , Adulto , Feminino , Genótipo , Humanos , Masculino , Mutação de Sentido Incorreto , Transtornos Psicóticos/genética , Transtornos Psicóticos/patologia
18.
Nat Genet ; 51(4): 592-599, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30926968

RESUMO

Transcriptome-wide association studies (TWAS) integrate genome-wide association studies (GWAS) and gene expression datasets to identify gene-trait associations. In this Perspective, we explore properties of TWAS as a potential approach to prioritize causal genes at GWAS loci, by using simulations and case studies of literature-curated candidate causal genes for schizophrenia, low-density-lipoprotein cholesterol and Crohn's disease. We explore risk loci where TWAS accurately prioritizes the likely causal gene as well as loci where TWAS prioritizes multiple genes, some likely to be non-causal, owing to sharing of expression quantitative trait loci (eQTL). TWAS is especially prone to spurious prioritization with expression data from non-trait-related tissues or cell types, owing to substantial cross-cell-type variation in expression levels and eQTL strengths. Nonetheless, TWAS prioritizes candidate causal genes more accurately than simple baselines. We suggest best practices for causal-gene prioritization with TWAS and discuss future opportunities for improvement. Our results showcase the strengths and limitations of using eQTL datasets to determine causal genes at GWAS loci.


Assuntos
Predisposição Genética para Doença/genética , Transcriptoma/genética , Doença de Crohn/genética , Variação Genética/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Lipoproteínas LDL/genética , Locos de Características Quantitativas/genética , Esquizofrenia/genética
19.
Nat Genet ; 51(4): 659-674, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30911161

RESUMO

Transcriptomic imputation approaches combine eQTL reference panels with large-scale genotype data in order to test associations between disease and gene expression. These genic associations could elucidate signals in complex genome-wide association study (GWAS) loci and may disentangle the role of different tissues in disease development. We used the largest eQTL reference panel for the dorso-lateral prefrontal cortex (DLPFC) to create a set of gene expression predictors and demonstrate their utility. We applied DLPFC and 12 GTEx-brain predictors to 40,299 schizophrenia cases and 65,264 matched controls for a large transcriptomic imputation study of schizophrenia. We identified 413 genic associations across 13 brain regions. Stepwise conditioning identified 67 non-MHC genes, of which 14 did not fall within previous GWAS loci. We identified 36 significantly enriched pathways, including hexosaminidase-A deficiency, and multiple porphyric disorder pathways. We investigated developmental expression patterns among the 67 non-MHC genes and identified specific groups of pre- and postnatal expression.


Assuntos
Encéfalo/fisiopatologia , Expressão Gênica/genética , Esquizofrenia/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Risco , Transcriptoma/genética
20.
Mol Genet Genomic Med ; 7(5): e652, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30908890

RESUMO

BACKGROUND: This study investigated the effects of haplotypes T-G and C-A derived from NG_012836.1:g.4160T>C and NG_012836.1:g.4326G>A on protein expression levels in vitro and identified the functional sequence in the regulatory region of the GABRB3 gene linked to possible associations with schizophrenia. METHODS: Recombinant plasmids with haplotypes T-G and C-A and 10 recombinant vectors containing deletion fragments from the GABRB3 gene 5' regulatory region were transfected into HEK-293, SK-N-SH, and SH-SY5Y cells. The relative fluorescence intensity of the two haplotypes and different sequences was compared using a dual luciferase reporter assay system. RESULTS: The relative fluorescence intensity of haplotype C-A was significantly lower than that of T-G. We shortened the core promoter sequence of the GABRB3 gene 5' regulation region from -177 bp to -18 bp (ATG+1). We also found an expression suppression region from -1,735 bp to -1,638 bp and an enhanced regulatory region from -1,638 bp to -1,335 bp. Multiple inhibitory functional elements were identified in the region from -680 bp to -177 bp. CONCLUSION: We demonstrated that haplotype C-A might increase the risk of schizophrenia and found multiple regulatory regions that had an effect on GABRB3 receptor expression.


Assuntos
Receptores de GABA-A/genética , Esquizofrenia/genética , Região 5'-Flanqueadora , Linhagem Celular Tumoral , Células HEK293 , Haplótipos , Humanos , Regiões Promotoras Genéticas , Receptores de GABA-A/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA