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1.
Phys Rev Lett ; 130(12): 123602, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37027846

RESUMO

We analyze an unusual class of bosonic dynamical instabilities that arise from dissipative (or non-Hermitian) pairing interactions. We show that, surprisingly, a completely stable dissipative pairing interaction can be combined with simple hopping or beam-splitter interactions (also stable) to generate instabilities. Further, we find that the dissipative steady state in such a situation remains completely pure up until the instability threshold (in clear distinction from standard parametric instabilities). These pairing-induced instabilities also exhibit an extremely pronounced sensitivity to wave function localization. This provides a simple yet powerful method for selectively populating and entangling edge modes of photonic (or more general bosonic) lattices having a topological band structure. The underlying dissipative pairing interaction is experimentally resource friendly, requiring the addition of a single additional localized interaction to an existing lattice, and is compatible with a number of existing platforms, including superconducting circuits.

2.
Hum Mol Genet ; 29(1): 159-167, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31691811

RESUMO

Schizophrenia is a complex highly heritable disorder. Genome-wide association studies (GWAS) have identified multiple loci that influence the risk of developing schizophrenia, although the causal variants driving these associations and their impacts on specific genes are largely unknown. We identify a significant correlation between schizophrenia risk and expression at 89 genes in the dorsolateral prefrontal cortex (P ≤ 9.43 × 10-6), including 20 novel genes. Genes whose expression correlate with schizophrenia were enriched for those involved in abnormal CNS synaptic transmission (PFDR = 0.02) and antigen processing and presentation of peptide antigen via MHC class I (PFDR = 0.02). Within the CNS synaptic transmission set, we identify individual significant candidate genes to which we assign direction of expression changes in schizophrenia. The findings provide strong candidates for experimentally probing the molecular basis of synaptic pathology in schizophrenia.


Assuntos
Esquizofrenia/genética , Esquizofrenia/patologia , Transcriptoma/genética , Encéfalo/metabolismo , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética
3.
Mol Psychiatry ; 26(7): 2977-2990, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33077856

RESUMO

Genes encoding the mRNA targets of fragile X mental retardation protein (FMRP) are enriched for genetic association with psychiatric disorders. However, many FMRP targets possess functions that are themselves genetically associated with psychiatric disorders, including synaptic transmission and plasticity, making it unclear whether the genetic risk is truly related to binding by FMRP or is alternatively mediated by the sampling of genes better characterised by another trait or functional annotation. Using published common variant, rare coding variant and copy number variant data, we examined the relationship between FMRP binding and genetic association with schizophrenia, major depressive disorder and bipolar disorder. High-confidence targets of FMRP, derived from studies of multiple tissue types, were enriched for common schizophrenia risk alleles, as well as rare loss-of-function and de novo nonsynonymous variants in schizophrenia cases. Similarly, through common variation, FMRP targets were associated with major depressive disorder, and we present novel evidence of association with bipolar disorder. These relationships could not be explained by other functional annotations known to be associated with psychiatric disorders, including those related to synaptic structure and function. This study reinforces the evidence that targeting by FMRP captures a subpopulation of genes enriched for genetic association with a range of psychiatric disorders.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Proteína do X Frágil da Deficiência Intelectual , Transtornos Mentais , Esquizofrenia , Transtorno Bipolar/genética , Transtorno Depressivo Maior/genética , Proteína do X Frágil da Deficiência Intelectual/genética , Humanos , Transtornos Mentais/genética , Esquizofrenia/genética
4.
Proc Natl Acad Sci U S A ; 116(19): 9604-9609, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31004051

RESUMO

Schizophrenia has been conceived as a disorder of brain connectivity, but it is unclear how this network phenotype is related to the underlying genetics. We used morphometric similarity analysis of MRI data as a marker of interareal cortical connectivity in three prior case-control studies of psychosis: in total, n = 185 cases and n = 227 controls. Psychosis was associated with globally reduced morphometric similarity in all three studies. There was also a replicable pattern of case-control differences in regional morphometric similarity, which was significantly reduced in patients in frontal and temporal cortical areas but increased in parietal cortex. Using prior brain-wide gene expression data, we found that the cortical map of case-control differences in morphometric similarity was spatially correlated with cortical expression of a weighted combination of genes enriched for neurobiologically relevant ontology terms and pathways. In addition, genes that were normally overexpressed in cortical areas with reduced morphometric similarity were significantly up-regulated in three prior post mortem studies of schizophrenia. We propose that this combined analysis of neuroimaging and transcriptional data provides insight into how previously implicated genes and proteins as well as a number of unreported genes in their topological vicinity on the protein interaction network may drive structural brain network changes mediating the genetic risk of schizophrenia.


Assuntos
Encéfalo , Regulação da Expressão Gênica , Rede Nervosa , Vias Neurais , Neuroimagem , Transtornos Psicóticos , Esquizofrenia , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/metabolismo , Rede Nervosa/patologia , Vias Neurais/metabolismo , Vias Neurais/patologia , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/metabolismo , Transtornos Psicóticos/patologia , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/metabolismo
5.
Nature ; 506(7487): 179-84, 2014 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-24463507

RESUMO

Inherited alleles account for most of the genetic risk for schizophrenia. However, new (de novo) mutations, in the form of large chromosomal copy number changes, occur in a small fraction of cases and disproportionally disrupt genes encoding postsynaptic proteins. Here we show that small de novo mutations, affecting one or a few nucleotides, are overrepresented among glutamatergic postsynaptic proteins comprising activity-regulated cytoskeleton-associated protein (ARC) and N-methyl-d-aspartate receptor (NMDAR) complexes. Mutations are additionally enriched in proteins that interact with these complexes to modulate synaptic strength, namely proteins regulating actin filament dynamics and those whose messenger RNAs are targets of fragile X mental retardation protein (FMRP). Genes affected by mutations in schizophrenia overlap those mutated in autism and intellectual disability, as do mutation-enriched synaptic pathways. Aligning our findings with a parallel case-control study, we demonstrate reproducible insights into aetiological mechanisms for schizophrenia and reveal pathophysiology shared with other neurodevelopmental disorders.


Assuntos
Modelos Neurológicos , Mutação/genética , Rede Nervosa/metabolismo , Vias Neurais/metabolismo , Esquizofrenia/genética , Esquizofrenia/fisiopatologia , Sinapses/metabolismo , Transtornos Globais do Desenvolvimento Infantil/genética , Proteínas do Citoesqueleto/metabolismo , Exoma/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Humanos , Deficiência Intelectual/genética , Taxa de Mutação , Rede Nervosa/fisiopatologia , Proteínas do Tecido Nervoso/metabolismo , Vias Neurais/fisiopatologia , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Esquizofrenia/metabolismo , Especificidade por Substrato
6.
Am J Med Genet B Neuropsychiatr Genet ; 180(1): 80-85, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30516002

RESUMO

A major controversy in psychiatric genetics is whether nonadditive genetic interaction effects contribute to the risk of highly polygenic disorders. We applied a support vector machines (SVMs) approach, which is capable of building linear and nonlinear models using kernel methods, to classify cases from controls in a large schizophrenia case-control sample of 11,853 subjects (5,554 cases and 6,299 controls) and compared its prediction accuracy with the polygenic risk score (PRS) approach. We also investigated whether SVMs are a suitable approach to detecting nonlinear genetic effects, that is, interactions. We found that PRS provided more accurate case/control classification than either linear or nonlinear SVMs, and give a tentative explanation why PRS outperforms both multivariate regression and linear kernel SVMs. In addition, we observe that nonlinear kernel SVMs showed higher classification accuracy than linear SVMs when a large number of SNPs are entered into the model. We conclude that SVMs are a potential tool for assessing the presence of interactions, prior to searching for them explicitly.


Assuntos
Esquizofrenia/diagnóstico , Esquizofrenia/genética , Algoritmos , Estudos de Casos e Controles , Simulação por Computador , Genoma/genética , Genômica , Humanos , Herança Multifatorial/genética , Fatores de Risco , Máquina de Vetores de Suporte
7.
Am J Med Genet B Neuropsychiatr Genet ; 174(7): 724-731, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28719003

RESUMO

Risk of schizophrenia is conferred by alleles occurring across the full spectrum of frequencies from common SNPs of weak effect through to ultra rare alleles, some of which may be moderately to highly penetrant. Previous studies have suggested that some of the risk of schizophrenia is attributable to uncommon alleles represented on Illumina exome arrays. Here, we present the largest study of exomic variation in schizophrenia to date, using samples from the United Kingdom and Sweden (10,011 schizophrenia cases and 13,791 controls). Single variants, genes, and gene sets were analyzed for association with schizophrenia. No single variant or gene reached genome-wide significance. Among candidate gene sets, we found significant enrichment for rare alleles (minor allele frequency [MAF] < 0.001) in genes intolerant of loss-of-function (LoF) variation and in genes whose messenger RNAs bind to fragile X mental retardation protein (FMRP). We further delineate the genetic architecture of schizophrenia by excluding a role for uncommon exomic variants (0.01 ≤ MAF ≥ 0.001) that confer a relatively large effect (odds ratio [OR] > 4). We also show risk alleles within this frequency range exist, but confer smaller effects and should be identified by larger studies.


Assuntos
Exoma , Proteína do X Frágil da Deficiência Intelectual/genética , Mutação , Polimorfismo de Nucleotídeo Único , Esquizofrenia/genética , Estudos de Casos e Controles , Estudos de Coortes , Seguimentos , Frequência do Gene , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Prognóstico
8.
Neuroimage ; 94: 147-154, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24642287

RESUMO

Variation in the CACNA1C gene has consistently been associated with psychosis in genome wide association studies. We have previously shown in a sample of n=110 healthy subjects that carriers of the CACNA1C rs1006737 risk variant exhibit hippocampal and perigenual anterior cingulate dysfunction (pgACC) during episodic memory recall. Here, we aimed to replicate our results, by testing for the effects of the rs1006737 risk variant in a new large cohort of healthy controls. We furthermore sought to refine these results by identifying the impact of a CACNA1C specific, gene-wide risk score in the absence of clinical pathology. An independent sample of 179 healthy subjects genotyped for rs1006737 underwent functional magnetic resonance imaging (fMRI) while performing an associative episodic memory task and underwent psychological testing similar to the discovery sample. The effect of gene-wide risk scores was analyzed in the combined sample of 289 subjects. We replicated our discovery findings of hippocampal and pgACC dysfunction in carriers of the rs1006737 risk variant. Additionally, we observed diminished activation of the dorsolateral prefrontal cortex, in the replication sample. Our replicated results as well as this new effect were also observable in the combined sample. Moreover, the same system-level phenotypes were significantly associated with the individual gene-based genetic risk score. Our findings suggest that altered hippocampal and frontolimbic function is associated with variants in the CACNA1C gene. Since CACNA1C variants have been associated repeatedly with psychosis at a genome-wide level, and preclinical data provide convergent evidence for the relevance of the CACNA1C gene for hippocampal and frontolimbic plasticity and adaptive regulation of stress, our data suggest a potential pathophysiological mechanism conferred by CACNA1C variants that may mediate risk for symptom dimensions shared among bipolar disorder, major depression, and schizophrenia.


Assuntos
Encéfalo/fisiopatologia , Canais de Cálcio Tipo L/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Memória Episódica , Rede Nervosa/fisiopatologia , Transtornos Psicóticos/genética , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Medição de Risco
9.
Eur J Neurosci ; 39(7): 1059-67, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24712986

RESUMO

It has been several decades since synaptic dysfunction was first suggested to play a role in schizophrenia, but only in the last few years has convincing evidence been obtained as progress has been made in elucidating the genetic underpinnings of the disorder. In the intervening years much has been learned concerning the complex macromolecular structure of the synapse itself, and genetic studies are now beginning to draw upon these advances. Here we outline our current understanding of the genetic architecture of schizophrenia and examine the evidence for synaptic involvement. A strong case can now be made that disruption of glutamatergic signalling pathways regulating synaptic plasticity contributes to the aetiology of schizophrenia.


Assuntos
Esquizofrenia/metabolismo , Sinapses/metabolismo , Animais , Variações do Número de Cópias de DNA , Humanos , Esquizofrenia/genética , Esquizofrenia/fisiopatologia , Sinapses/fisiologia , Transmissão Sináptica
10.
Cell Rep ; 43(3): 113946, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38483902

RESUMO

The mechanisms by which genomic risks contribute to the onset of neuropsychiatric conditions remain a key challenge and a prerequisite for successful development of effective therapies. 15q11.2 copy number variation (CNV) containing the CYFIP1 gene is associated with autism and schizophrenia. Using stem cell models, we show that 15q11.2 deletion (15q11.2del) and CYFIP1 loss of function (CYFIP1-LoF) lead to premature neuronal differentiation, while CYFIP1 gain of function (CYFIP1-GoF) favors neural progenitor maintenance. CYFIP1 dosage changes led to dysregulated cholesterol metabolism and altered levels of 24S,25-epoxycholesterol, which can mimic the 15q11.2del and CYFIP1-LoF phenotypes by promoting cortical neuronal differentiation and can restore the impaired neuronal differentiation of CYFIP1-GoF neural progenitors. Moreover, the neurogenic activity of 24S,25-epoxycholesterol is lost following genetic deletion of liver X receptor (LXRß), while compound deletion of LXRß in CYFIP1-/- background rescued their premature neurogenesis. This work delineates LXR-mediated oxysterol regulation of neurogenesis as a pathological mechanism in neural cells carrying 15q11.2 CNV and provides a potential target for therapeutic strategies for associated disorders.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Transtorno Autístico , Humanos , Receptores X do Fígado/genética , Receptores X do Fígado/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Variações do Número de Cópias de DNA , Transtorno Autístico/genética , Células-Tronco/metabolismo , Neurogênese
11.
Nat Neurosci ; 11(7): 799-806, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18536710

RESUMO

Understanding the origins and evolution of synapses may provide insight into species diversity and the organization of the brain. Using comparative proteomics and genomics, we examined the evolution of the postsynaptic density (PSD) and membrane-associated guanylate kinase (MAGUK)-associated signaling complexes (MASCs) that underlie learning and memory. PSD and MASC orthologs found in yeast carry out basic cellular functions to regulate protein synthesis and structural plasticity. We observed marked changes in signaling complexity at the yeast-metazoan and invertebrate-vertebrate boundaries, with an expansion of key synaptic components, notably receptors, adhesion/cytoskeletal proteins and scaffold proteins. A proteomic comparison of Drosophila and mouse MASCs revealed species-specific adaptation with greater signaling complexity in mouse. Although synaptic components were conserved amongst diverse vertebrate species, mapping mRNA and protein expression in the mouse brain showed that vertebrate-specific components preferentially contributed to differences between brain regions. We propose that the evolution of synapse complexity around a core proto-synapse has contributed to invertebrate-vertebrate differences and to brain specialization.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Estudos de Avaliação como Assunto , Proteínas do Tecido Nervoso/metabolismo , Proteoma , Sinapses/metabolismo , Animais , Proteínas Reguladoras de Apoptose , Comportamento Animal , Encéfalo/citologia , Encéfalo/metabolismo , Mapeamento Encefálico , Proteínas Adaptadoras de Sinalização CARD , Proteínas do Citoesqueleto/genética , Drosophila , Expressão Gênica , Camundongos , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Proteômica/métodos , Transdução de Sinais/fisiologia
12.
Nat Commun ; 13(1): 27, 2022 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-35031607

RESUMO

Coordinated programs of gene expression drive brain development. It is unclear which transcriptional programs, in which cell-types, are affected in neuropsychiatric disorders such as schizophrenia. Here we integrate human genetics with transcriptomic data from differentiation of human embryonic stem cells into cortical excitatory neurons. We identify transcriptional programs expressed during early neurogenesis in vitro and in human foetal cortex that are down-regulated in DLG2-/- lines. Down-regulation impacted neuronal differentiation and maturation, impairing migration, morphology and action potential generation. Genetic variation in these programs is associated with neuropsychiatric disorders and cognitive function, with associated variants predominantly concentrated in loss-of-function intolerant genes. Neurogenic programs also overlap schizophrenia GWAS enrichment previously identified in mature excitatory neurons, suggesting that pathways active during prenatal cortical development may also be associated with mature neuronal dysfunction. Our data from human embryonic stem cells, when combined with analysis of available foetal cortical gene expression data, de novo rare variants and GWAS statistics for neuropsychiatric disorders and cognition, reveal a convergence on transcriptional programs regulating excitatory cortical neurogenesis.


Assuntos
Córtex Cerebral/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Guanilato Quinases/genética , Neurogênese , Proteínas Supressoras de Tumor/genética , Animais , Diferenciação Celular , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Predisposição Genética para Doença , Guanilato Quinases/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Transtornos Mentais/genética , Neurogênese/genética , Neurogênese/fisiologia , Neurônios , Gravidez , Esquizofrenia/genética , Transcriptoma , Proteínas Supressoras de Tumor/metabolismo
13.
Biol Psychiatry ; 90(1): 28-34, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33678419

RESUMO

BACKGROUND: Cognitive impairment in schizophrenia is a major contributor to poor outcomes, yet its causes are poorly understood. Some rare copy number variants (CNVs) are associated with schizophrenia risk and affect cognition in healthy populations, but their contribution to cognitive impairment in schizophrenia has not been investigated. We examined the effect of 12 schizophrenia CNVs on cognition in those with schizophrenia. METHODS: General cognitive ability was measured using the Measurement and Treatment Research to Improve Cognition in Schizophrenia composite z score in 875 patients with schizophrenia and in a replication sample of 519 patients with schizophrenia using Wechsler Adult Intelligence Scale Full Scale IQ. Using linear regression, we tested for association between cognition and schizophrenia CNV status, covarying for age and sex. In addition, we tested whether CNVs hitting genes in schizophrenia-enriched gene sets (loss-of-function intolerant and synaptic gene sets) were associated with cognitive impairment. RESULTS: A total of 23 schizophrenia CNV carriers were identified. Schizophrenia CNV carriers had lower general cognitive ability than nonschizophrenia CNV carriers in discovery (ß = -0.66, 95% confidence interval [CI] = -1.31 to -0.01) and replication samples (ß = -0.91, 95% CI = -1.71 to -0.11) and after meta-analysis (ß = -0.76, 95% CI = -1.26 to -0.25, p = .003). CNVs hitting loss-of-function intolerant genes were associated with lower cognition (ß = -0.15, 95% CI = -0.29 to -0.001, p = .048). CONCLUSIONS: In those with schizophrenia, cognitive ability in schizophrenia CNV carriers is 0.5-1.0 standard deviations below non-CNV carriers, which may have implications for clinical assessment and management. We also demonstrate that rare CNVs hitting genes intolerant to loss-of-function variation lead to more severe cognitive impairment, above and beyond the effect of known schizophrenia CNVs.


Assuntos
Esquizofrenia , Adulto , Cognição , Variações do Número de Cópias de DNA/genética , Predisposição Genética para Doença , Humanos , Testes de Inteligência , Fenótipo , Esquizofrenia/complicações , Esquizofrenia/genética
14.
Transl Psychiatry ; 10(1): 309, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908133

RESUMO

Research has shown differences in subcortical brain volumes between participants with schizophrenia and healthy controls. However, none of these differences have been found to associate with schizophrenia polygenic risk. Here, in a large sample (n = 14,701) of unaffected participants from the UK Biobank, we test whether schizophrenia polygenic risk scores (PRS) limited to specific gene-sets predict subcortical brain volumes. We compare associations with schizophrenia PRS at the whole genome level ('genomic', including all SNPs associated with the disorder at a p-value threshold < 0.05) with 'genic' PRS (based on SNPs in the vicinity of known genes), 'intergenic' PRS (based on the remaining SNPs), and genic PRS limited to SNPs within 7 gene-sets previously found to be enriched for genetic association with schizophrenia ('abnormal behaviour,' 'abnormal long-term potentiation,' 'abnormal nervous system electrophysiology,' 'FMRP targets,' '5HT2C channels,' 'CaV2 channels' and 'loss-of-function intolerant genes'). We observe a negative association between the 'abnormal behaviour' gene-set PRS and volume of the right thalamus that survived correction for multiple testing (ß = -0.031, pFDR = 0.005) and was robust to different schizophrenia PRS p-value thresholds. In contrast, the only association with genomic PRS surviving correction for multiple testing was for right pallidum, which was observed using a schizophrenia PRS p-value threshold < 0.01 (ß = -0.032, p = 0.0003, pFDR = 0.02), but not when using other PRS P-value thresholds. We conclude that schizophrenia PRS limited to functional gene sets may provide a better means of capturing differences in subcortical brain volume than whole genome PRS approaches.


Assuntos
Esquizofrenia , Bancos de Espécimes Biológicos , Encéfalo/diagnóstico por imagem , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Herança Multifatorial , Esquizofrenia/genética , Reino Unido
15.
Nat Neurosci ; 23(2): 179-184, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31932766

RESUMO

Schizophrenia is a highly polygenic disorder with important contributions from both common and rare risk alleles. We analyzed exome sequencing data for de novo variants (DNVs) in a new sample of 613 schizophrenia trios and combined this with published data to give a total of 3,444 trios. In this new data, loss-of-function (LoF) DNVs were significantly enriched among 3,471 LoF-intolerant genes, which supports previous findings. In the full dataset, genes associated with neurodevelopmental disorders (n = 159) were significantly enriched for LoF DNVs. Within these neurodevelopmental disorder genes, SLC6A1, which encodes a γ-aminobutyric acid transporter, was associated with missense-damaging DNVs. In 1,122 trios for which genome-wide common variant data were available, schizophrenia and bipolar disorder polygenic risk were significantly overtransmitted to probands. Probands carrying LoF or deletion DNVs in LoF-intolerant or neurodevelopmental disorder genes had significantly less overtransmission of schizophrenia polygenic risk than did non-carriers, which provides a second robust line of evidence that these DNVs increase liability to schizophrenia.


Assuntos
Proteínas da Membrana Plasmática de Transporte de GABA/genética , Predisposição Genética para Doença/genética , Esquizofrenia/genética , Adulto , Feminino , Humanos , Masculino , Mutação de Sentido Incorreto , Sequenciamento do Exoma
16.
Biol Psychiatry ; 86(4): 265-273, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31230729

RESUMO

BACKGROUND: A recent genome-wide association study (GWAS) of autism spectrum disorder (ASD) (ncases = 18,381, ncontrols = 27,969) has provided novel opportunities for investigating the etiology of ASD. Here, we integrate the ASD GWAS summary statistics with summary-level gene expression data to infer differential gene expression in ASD, an approach called transcriptome-wide association study (TWAS). METHODS: Using FUSION software, ASD GWAS summary statistics were integrated with predictors of gene expression from 16 human datasets, including adult and fetal brains. A novel adaptation of established statistical methods was then used to test for enrichment within candidate pathways and specific tissues and at different stages of brain development. The proportion of ASD heritability explained by predicted expression of genes in the TWAS was estimated using stratified linkage disequilibrium score regression. RESULTS: This study identified 14 genes as significantly differentially expressed in ASD, 13 of which were outside of known genome-wide significant loci (±500 kb). XRN2, a gene proximal to an ASD GWAS locus, was inferred to be significantly upregulated in ASD, providing insight into the functional consequence of this associated locus. One novel transcriptome-wide significant association from this study is the downregulation of PDIA6, which showed minimal evidence of association in the GWAS, and in gene-based analysis using MAGMA. Predicted gene expression in this study accounted for 13.0% of the total ASD single nucleotide polymorphism heritability. CONCLUSIONS: This study has implicated several genes as significantly up/downregulated in ASD, providing novel and useful information for subsequent functional studies. This study also explores the utility of TWAS-based enrichment analysis and compares TWAS results with a functionally agnostic approach.


Assuntos
Transtorno do Espectro Autista/genética , Estudo de Associação Genômica Ampla , Transcriptoma , Exorribonucleases/genética , Genômica , Humanos , Isomerases de Dissulfetos de Proteínas/genética
17.
Transl Psychiatry ; 9(1): 74, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718481

RESUMO

Common genetic variation contributes a substantial proportion of risk for both schizophrenia and bipolar disorder. Furthermore, there is evidence of significant, but not complete, overlap in genetic risk between the two disorders. It has been hypothesised that genetic variants conferring risk for these disorders do so by influencing brain development, leading to the later emergence of symptoms. The comparative profile of risk gene expression for schizophrenia and bipolar disorder across development over different brain regions however remains unclear. Using genotypes derived from genome-wide associations studies of the largest available cohorts of patients and control subjects, we investigated whether genes enriched for schizophrenia and bipolar disorder association show a bias for expression across any of 13 developmental stages in prefrontal cortical and subcortical brain regions. We show that genetic association with schizophrenia is positively correlated with expression in the prefrontal cortex during early midfetal development and early infancy, and negatively correlated with expression during late childhood, which stabilises in adolescence. In contrast, risk-associated genes for bipolar disorder did not exhibit a bias towards expression at any prenatal stage, although the pattern of postnatal expression was similar to that of schizophrenia. These results highlight the dynamic expression of genes harbouring risk for schizophrenia and bipolar disorder across prefrontal cortex development and support the hypothesis that prenatal neurodevelopmental events are more strongly associated with schizophrenia than bipolar disorder.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Transtorno Bipolar/genética , Transtorno Bipolar/metabolismo , Desenvolvimento Infantil/fisiologia , Desenvolvimento Fetal/fisiologia , Perfilação da Expressão Gênica , Expressão Gênica/genética , Predisposição Genética para Doença , Córtex Pré-Frontal/crescimento & desenvolvimento , Córtex Pré-Frontal/metabolismo , Esquizofrenia/genética , Adolescente , Adulto , Criança , Pré-Escolar , Estudo de Associação Genômica Ampla , Humanos , Lactente , Adulto Jovem
18.
Schizophr Bull ; 45(2): 405-414, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-29608775

RESUMO

Risk profile scores (RPS) derived from genome-wide association studies (GWAS) explain a considerable amount of susceptibility for schizophrenia (SCZ). However, little is known about how common genetic risk factors for SCZ influence the structure and function of the human brain, largely due to the constraints of imaging sample sizes. In the current study, we use a novel recall-by-genotype (RbG) methodological approach, where we sample young adults from a population cohort (Avon Longitudinal Study of Parents and Children: N genotyped = 8365) based on their SCZ-RPS. We compared 197 healthy individuals at extremes of low (N = 99) or high (N = 98) SCZ-RPS with behavioral tests, and structural and functional magnetic resonance imaging (fMRI). We first provide methodological details that will inform the design of future RbG studies for common SCZ genetic risk. We further provide an between group analysis of the RbG individuals (low vs high SCZ-RPS) who underwent structural neuroimaging data (T1-weighted scans) and fMRI data during a reversal learning task. While we found little evidence for morphometric differences between the low and high SCZ-RPS groups, we observed an impact of SCZ-RPS on blood oxygen level-dependent (BOLD) signal during reward processing in the ventral striatum (PFWE-VS-CORRECTED = .037), a previously investigated broader reward-related network (PFWE-ROIS-CORRECTED = .008), and across the whole brain (PFWE-WHOLE-BRAIN-CORRECTED = .013). We also describe the study strategy and discuss specific challenges of RbG for SCZ risk (such as SCZ-RPS related homoscedasticity). This study will help to elucidate the behavioral and imaging phenotypes that are associated with SCZ genetic risk.


Assuntos
Encéfalo , Predisposição Genética para Doença , Genótipo , Neuroimagem/métodos , Reversão de Aprendizagem/fisiologia , Esquizofrenia , Estriado Ventral , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/fisiopatologia , Estudos de Coortes , Feminino , Neuroimagem Funcional/métodos , Predisposição Genética para Doença/genética , Humanos , Imageamento por Ressonância Magnética , Masculino , Recompensa , Risco , Esquizofrenia/genética , Esquizofrenia/patologia , Esquizofrenia/fisiopatologia , Estriado Ventral/diagnóstico por imagem , Estriado Ventral/patologia , Estriado Ventral/fisiopatologia , Adulto Jovem
19.
Am J Psychiatry ; 176(6): 477-486, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30922102

RESUMO

OBJECTIVE: Clozapine is the only effective medication for treatment-resistant schizophrenia, but its worldwide use is still limited because of its complex titration protocols. While the discovery of pharmacogenomic variants of clozapine metabolism may improve clinical management, no robust findings have yet been reported. This study is the first to adopt the framework of genome-wide association studies (GWASs) to discover genetic markers of clozapine plasma concentrations in a large sample of patients with treatment-resistant schizophrenia. METHODS: The authors used mixed-model regression to combine data from multiple assays of clozapine metabolite plasma concentrations from a clozapine monitoring service and carried out a genome-wide analysis of clozapine, norclozapine, and their ratio on 10,353 assays from 2,989 individuals. These analyses were adjusted for demographic factors known to influence clozapine metabolism, although it was not possible to adjust for all potential mediators given the available data. GWAS results were used to pinpoint specific enzymes and metabolic pathways and compounds that might interact with clozapine pharmacokinetics. RESULTS: The authors identified four distinct genome-wide significant loci that harbor common variants affecting the metabolism of clozapine or its metabolites. Detailed examination pointed to coding and regulatory variants at several CYP* and UGT* genes as well as corroborative evidence for interactions between the metabolism of clozapine, coffee, and tobacco. Individual effects of single single-nucleotide polymorphisms (SNPs) fine-mapped from these loci were large, such as the minor allele of rs2472297, which was associated with a reduction in clozapine concentrations roughly equivalent to a decrease of 50 mg/day in clozapine dosage. On their own, these single SNPs explained from 1.15% to 9.48% of the variance in the plasma concentration data. CONCLUSIONS: Common genetic variants with large effects on clozapine metabolism exist and can be found via genome-wide approaches. Their identification opens the way for clinical studies assessing the use of pharmacogenomics in the clinical management of patients with treatment-resistant schizophrenia.


Assuntos
Clozapina/análogos & derivados , Clozapina/metabolismo , Esquizofrenia/tratamento farmacológico , Adulto , Antipsicóticos/uso terapêutico , Clozapina/uso terapêutico , Café , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A2/genética , Interações Medicamentosas , Feminino , Estudo de Associação Genômica Ampla , Glucuronosiltransferase/genética , Humanos , Masculino , Variantes Farmacogenômicos , Polimorfismo de Nucleotídeo Único , Nicotiana
20.
Biol Psychiatry ; 85(7): 554-562, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30420267

RESUMO

BACKGROUND: Sequencing studies have pointed to the involvement in schizophrenia of rare coding variants in neuronally expressed genes, including activity-regulated cytoskeleton-associated protein (ARC) and N-methyl-D-aspartate receptor (NMDAR) complexes; however, larger samples are required to reveal novel genes and specific biological mechanisms. METHODS: We sequenced 187 genes, selected for prior evidence of association with schizophrenia, in a new dataset of 5207 cases and 4991 controls. Included among these genes were members of ARC and NMDAR postsynaptic protein complexes, as well as voltage-gated sodium and calcium channels. We performed a rare variant meta-analysis with published sequencing data for a total of 11,319 cases, 15,854 controls, and 1136 trios. RESULTS: While no individual gene was significantly associated with schizophrenia after genome-wide correction for multiple testing, we strengthen the evidence that rare exonic variants in the ARC (p = 4.0 × 10-4) and NMDAR (p = 1.7 × 10-5) synaptic complexes are risk factors for schizophrenia. In addition, we found that loss-of-function variants and missense variants at paralog-conserved sites were enriched in voltage-gated sodium channels, particularly the alpha subunits (p = 8.6 × 10-4). CONCLUSIONS: In one of the largest sequencing studies of schizophrenia to date, we provide novel evidence that multiple voltage-gated sodium channels are involved in schizophrenia pathogenesis and confirm the involvement of ARC and NMDAR postsynaptic complexes.


Assuntos
Proteínas do Citoesqueleto/genética , Proteínas do Tecido Nervoso/genética , Neurônios/fisiologia , Receptores de N-Metil-D-Aspartato/genética , Esquizofrenia/genética , Esquizofrenia/fisiopatologia , Análise de Sequência de DNA , Canais de Sódio Disparados por Voltagem/genética , Adulto , Estudos de Coortes , Humanos , Irlanda , Pessoa de Meia-Idade , Países Baixos , Fatores de Risco , Reino Unido
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