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1.
Proc Natl Acad Sci U S A ; 120(31): e2215632120, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37506195

RESUMO

Autism spectrum disorder (ASD) has a complex genetic architecture involving contributions from both de novo and inherited variation. Few studies have been designed to address the role of rare inherited variation or its interaction with common polygenic risk in ASD. Here, we performed whole-genome sequencing of the largest cohort of multiplex families to date, consisting of 4,551 individuals in 1,004 families having two or more autistic children. Using this study design, we identify seven previously unrecognized ASD risk genes supported by a majority of rare inherited variants, finding support for a total of 74 genes in our cohort and a total of 152 genes after combined analysis with other studies. Autistic children from multiplex families demonstrate an increased burden of rare inherited protein-truncating variants in known ASD risk genes. We also find that ASD polygenic score (PGS) is overtransmitted from nonautistic parents to autistic children who also harbor rare inherited variants, consistent with combinatorial effects in the offspring, which may explain the reduced penetrance of these rare variants in parents. We also observe that in addition to social dysfunction, language delay is associated with ASD PGS overtransmission. These results are consistent with an additive complex genetic risk architecture of ASD involving rare and common variation and further suggest that language delay is a core biological feature of ASD.


Assuntos
Transtorno do Espectro Autista , Transtornos do Desenvolvimento da Linguagem , Criança , Humanos , Transtorno do Espectro Autista/genética , Herança Multifatorial/genética , Pais , Sequenciamento Completo do Genoma , Predisposição Genética para Doença
2.
J Am Acad Child Adolesc Psychiatry ; 62(9): 949-952, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37196781

RESUMO

Among the many race-based health disparities that have persistently plagued the US population,1 the disproportionate burden of adverse neurodevelopmental outcomes to Black children affected by autism spectrum disorder (ASD) is particularly devastating given its major lifelong consequences. Recently, in 3 successive reports from the Autism and Developmental Disabilities Monitoring (ADDM) program of the US Centers for Disease Control and Prevention (CDC) (birth cohort years 2014, 2016, and 2018), we and our collaborators reported that although the prevalence of community-diagnosed ASD had equalized for Black and non-Hispanic White (NHW) children in the United States, there has persisted a pronounced racial disparity in the proportion of ASD-affected children with comorbid intellectual disability (ID), on the order of 50% for Black children with ASD vs 20% for White children with ASD.2 Here, we provide data to support the following: much earlier diagnosis is possible; early diagnosis alone is not likely to close the ID comorbidity disparity; and judicious efforts over care as usual are necessary to ensure that Black children have access to timely implementation of developmental therapy, for which we observed promising associations with improved cognitive and adaptive outcomes in our sample.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Deficiência Intelectual , Humanos , Criança , Estados Unidos/epidemiologia , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/epidemiologia , Transtorno Autístico/epidemiologia , Prevalência , Comorbidade , Deficiência Intelectual/epidemiologia
3.
Brain ; 145(1): 378-387, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-34050743

RESUMO

The biological mechanisms underlying the greater prevalence of autism spectrum disorder in males than females remain poorly understood. One hypothesis posits that this female protective effect arises from genetic load for autism spectrum disorder differentially impacting male and female brains. To test this hypothesis, we investigated the impact of cumulative genetic risk for autism spectrum disorder on functional brain connectivity in a balanced sample of boys and girls with autism spectrum disorder and typically developing boys and girls (127 youth, ages 8-17). Brain connectivity analyses focused on the salience network, a core intrinsic functional connectivity network which has previously been implicated in autism spectrum disorder. The effects of polygenic risk on salience network functional connectivity were significantly modulated by participant sex, with genetic load for autism spectrum disorder influencing functional connectivity in boys with and without autism spectrum disorder but not girls. These findings support the hypothesis that autism spectrum disorder risk genes interact with sex differential processes, thereby contributing to the male bias in autism prevalence and proposing an underlying neurobiological mechanism for the female protective effect.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Adolescente , Transtorno do Espectro Autista/genética , Transtorno Autístico/genética , Encéfalo , Mapeamento Encefálico , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
4.
Pediatrics ; 146(3)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32839243

RESUMO

OBJECTIVES: African American (AA) children affected by autism spectrum disorder (ASD) experience delays in diagnosis and obstacles to service access, as well as a disproportionate burden of intellectual disability (ID) as documented in surveillance data recently published by the US Centers for Disease Control and Prevention. Our objective in this study was to analyze data from the largest-available repository of diagnostic and phenotypic information on AA children with ASD, and to explore the wide variation in outcome within the cohort as a function of sociodemographic risk and specific obstacles to service access for the purpose of informing a national approach to resolution of these disparities. METHODS: Parents of 584 AA children with autism consecutively enrolled in the Autism Genetic Resource Exchange across 4 US data collection sites completed event history calendar interviews of the diagnostic odysseys for their children with ASD. These data were examined in relation to developmental outcomes of the children with autism and their unaffected siblings. RESULTS: The average age of ASD diagnosis was 64.9 months (±49.6), on average 42.3 months (±45.1) after parents' first concerns about their children's development. The relationship between timing of diagnosis and ASD severity was complex, and ID comorbidity was not predicted in a straightforward manner by familial factors associated with cognitive variation in the general population. CONCLUSIONS: These findings document significant opportunity to expedite diagnosis, the need to further understand causes of ID comorbidity, and the necessity to identify effective approaches to the resolution of disparities in severity-of-outcome for AA children with autism.


Assuntos
Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/genética , Negro ou Afro-Americano/genética , Bases de Dados Genéticas/tendências , Diagnóstico Tardio/tendências , Negro ou Afro-Americano/psicologia , Fatores Etários , Transtorno do Espectro Autista/psicologia , Criança , Pré-Escolar , Diagnóstico Tardio/prevenção & controle , Diagnóstico Tardio/psicologia , Feminino , Humanos , Masculino
5.
Transl Psychiatry ; 10(1): 82, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127526

RESUMO

Autism spectrum disorder (ASD) is more prevalent in males than in females, but the neurobiological mechanisms that give rise to this sex-bias are poorly understood. The female protective hypothesis suggests that the manifestation of ASD in females requires higher cumulative genetic and environmental risk relative to males. Here, we test this hypothesis by assessing the additive impact of several ASD-associated OXTR variants on reward network resting-state functional connectivity in males and females with and without ASD, and explore how genotype, sex, and diagnosis relate to heterogeneity in neuroendophenotypes. Females with ASD who carried a greater number of ASD-associated risk alleles in the OXTR gene showed greater functional connectivity between the nucleus accumbens (NAcc; hub of the reward network) and subcortical brain areas important for motor learning. Relative to males with ASD, females with ASD and higher OXTR risk-allele-dosage showed increased connectivity between the NAcc, subcortical regions, and prefrontal brain areas involved in mentalizing. This increased connectivity between NAcc and prefrontal cortex mirrored the relationship between genetic risk and brain connectivity observed in neurotypical males showing that, under increased OXTR genetic risk load, females with ASD and neurotypical males displayed increased connectivity between reward-related brain regions and prefrontal cortex. These results indicate that females with ASD differentially modulate the effects of increased genetic risk on brain connectivity relative to males with ASD, providing new insights into the neurobiological mechanisms through which the female protective effect may manifest.


Assuntos
Transtorno do Espectro Autista , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/genética , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/metabolismo , Receptores de Ocitocina/genética , Receptores de Ocitocina/metabolismo , Recompensa , Caracteres Sexuais
6.
Cell ; 178(4): 850-866.e26, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398340

RESUMO

We performed a comprehensive assessment of rare inherited variation in autism spectrum disorder (ASD) by analyzing whole-genome sequences of 2,308 individuals from families with multiple affected children. We implicate 69 genes in ASD risk, including 24 passing genome-wide Bonferroni correction and 16 new ASD risk genes, most supported by rare inherited variants, a substantial extension of previous findings. Biological pathways enriched for genes harboring inherited variants represent cytoskeletal organization and ion transport, which are distinct from pathways implicated in previous studies. Nevertheless, the de novo and inherited genes contribute to a common protein-protein interaction network. We also identified structural variants (SVs) affecting non-coding regions, implicating recurrent deletions in the promoters of DLG2 and NR3C2. Loss of nr3c2 function in zebrafish disrupts sleep and social function, overlapping with human ASD-related phenotypes. These data support the utility of studying multiplex families in ASD and are available through the Hartwell Autism Research and Technology portal.


Assuntos
Transtorno do Espectro Autista/genética , Predisposição Genética para Doença/genética , Linhagem , Mapas de Interação de Proteínas/genética , Animais , Criança , Bases de Dados Genéticas , Modelos Animais de Doenças , Feminino , Deleção de Genes , Guanilato Quinases/genética , Humanos , Padrões de Herança/genética , Aprendizado de Máquina , Masculino , Núcleo Familiar , Regiões Promotoras Genéticas/genética , Receptores de Mineralocorticoides/genética , Fatores de Risco , Proteínas Supressoras de Tumor/genética , Sequenciamento Completo do Genoma , Peixe-Zebra/genética
7.
Neuron ; 103(5): 785-801.e8, 2019 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-31303374

RESUMO

We performed RNA sequencing on 40,000 cells to create a high-resolution single-cell gene expression atlas of developing human cortex, providing the first single-cell characterization of previously uncharacterized cell types, including human subplate neurons, comparisons with bulk tissue, and systematic analyses of technical factors. These data permit deconvolution of regulatory networks connecting regulatory elements and transcriptional drivers to single-cell gene expression programs, significantly extending our understanding of human neurogenesis, cortical evolution, and the cellular basis of neuropsychiatric disease. We tie cell-cycle progression with early cell fate decisions during neurogenesis, demonstrating that differentiation occurs on a transcriptomic continuum; rather than only expressing a few transcription factors that drive cell fates, differentiating cells express broad, mixed cell-type transcriptomes before telophase. By mapping neuropsychiatric disease genes to cell types, we implicate dysregulation of specific cell types in ASD, ID, and epilepsy. We developed CoDEx, an online portal to facilitate data access and browsing.


Assuntos
Bases de Dados Genéticas , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes/genética , Neocórtex/embriologia , Neurogênese/genética , Neurônios/metabolismo , Transtorno do Espectro Autista/genética , Ciclo Celular , Córtex Cerebral/citologia , Córtex Cerebral/embriologia , Córtex Cerebral/metabolismo , Células Ependimogliais/metabolismo , Epilepsia/embriologia , Epilepsia/genética , Feminino , Perfilação da Expressão Gênica , Idade Gestacional , Humanos , Deficiência Intelectual/embriologia , Deficiência Intelectual/genética , Interneurônios/metabolismo , Neocórtex/citologia , Neocórtex/metabolismo , Células-Tronco Neurais/metabolismo , Gravidez , Segundo Trimestre da Gravidez , RNA-Seq , Análise de Célula Única , Telófase/genética
8.
Mov Disord ; 34(7): 1049-1059, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31059154

RESUMO

BACKGROUND: Progressive supranuclear palsy is a neurodegenerative tauopathy manifesting clinically as a progressive akinetic-rigid syndrome. In this study, we sought to identify genetic variants influencing PSP susceptibility through a genome-wide association analysis of a cohort of well-characterized patients who had participated in the Neuroprotection and Natural History in Parkinson Plus Syndromes and Blood Brain Barrier in Parkinson Plus Syndromes studies. METHODS: We genotyped single-nucleotide polymorphisms in 283 PSP cases from the United Kingdom, Germany, and France and compared these with genotypes from 4472 controls. Copy number variants were identified from genotyping data. RESULTS: We observed associations on chromosome 17 within or close to the MAPT gene and explored the genetic architecture at this locus. We confirmed the previously reported association of rs1768208 in the MOBP gene (P = 3.29 × 10-13 ) and rs1411478 in STX6 (P = 3.45 × 10-10 ). The population-attributable risk from the MAPT, MOBP, and STX6 single-nucleotide polymorphisms was found to be 0.37, 0.26, and 0.08, respectively. In addition, we found 2 instances of copy number variants spanning the MAPT gene in patients with PSP. These copy number variants include tau but few other genes within the chromosome 17 haplotype region, providing additional support for the direct pathogenicity of MAPT in PSP. CONCLUSIONS: Clinicians should also be aware of MAPT duplication as a possible genetic cause of PSP, especially in patients presenting with young age at onset. © 2019 International Parkinson and Movement Disorder Society.


Assuntos
Variações do Número de Cópias de DNA/genética , Genótipo , Paralisia Supranuclear Progressiva/genética , Proteínas tau/genética , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
9.
Mol Neurodegener ; 13(1): 41, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-30089514

RESUMO

BACKGROUND: Progressive supranuclear palsy (PSP) is a rare neurodegenerative disease for which the genetic contribution is incompletely understood. METHODS: We conducted a joint analysis of 5,523,934 imputed SNPs in two newly-genotyped progressive supranuclear palsy cohorts, primarily derived from two clinical trials (Allon davunetide and NNIPPS riluzole trials in PSP) and a previously published genome-wide association study (GWAS), in total comprising 1646 cases and 10,662 controls of European ancestry. RESULTS: We identified 5 associated loci at a genome-wide significance threshold P < 5 × 10- 8, including replication of 3 loci from previous studies and 2 novel loci at 6p21.1 and 12p12.1 (near RUNX2 and SLCO1A2, respectively). At the 17q21.31 locus, stepwise regression analysis confirmed the presence of multiple independent loci (localized near MAPT and KANSL1). An additional 4 loci were highly suggestive of association (P < 1 × 10- 6). We analyzed the genetic correlation with multiple neurodegenerative diseases, and found that PSP had shared polygenic heritability with Parkinson's disease and amyotrophic lateral sclerosis. CONCLUSIONS: In total, we identified 6 additional significant or suggestive SNP associations with PSP, and discovered genetic overlap with other neurodegenerative diseases. These findings clarify the pathogenesis and genetic architecture of PSP.


Assuntos
Predisposição Genética para Doença/genética , Doenças Neurodegenerativas/genética , Paralisia Supranuclear Progressiva/genética , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Polimorfismo de Nucleotídeo Único
10.
Nature ; 560(7718): E30, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29995847

RESUMO

Change history: In this Letter, the labels for splicing events A3SS and A5SS were swapped in column D of Supplementary Table 3a and b. This has been corrected online.

11.
Nature ; 540(7633): 423-427, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27919067

RESUMO

Autism spectrum disorder (ASD) involves substantial genetic contributions. These contributions are profoundly heterogeneous but may converge on common pathways that are not yet well understood. Here, through post-mortem genome-wide transcriptome analysis of the largest cohort of samples analysed so far, to our knowledge, we interrogate the noncoding transcriptome, alternative splicing, and upstream molecular regulators to broaden our understanding of molecular convergence in ASD. Our analysis reveals ASD-associated dysregulation of primate-specific long noncoding RNAs (lncRNAs), downregulation of the alternative splicing of activity-dependent neuron-specific exons, and attenuation of normal differences in gene expression between the frontal and temporal lobes. Our data suggest that SOX5, a transcription factor involved in neuron fate specification, contributes to this reduction in regional differences. We further demonstrate that a genetically defined subtype of ASD, chromosome 15q11.2-13.1 duplication syndrome (dup15q), shares the core transcriptomic signature observed in idiopathic ASD. Co-expression network analysis reveals that individuals with ASD show age-related changes in the trajectory of microglial and synaptic function over the first two decades, and suggests that genetic risk for ASD may influence changes in regional cortical gene expression. Our findings illustrate how diverse genetic perturbations can lead to phenotypic convergence at multiple biological levels in a complex neuropsychiatric disorder.


Assuntos
Processamento Alternativo/genética , Transtorno do Espectro Autista/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genoma Humano/genética , RNA Longo não Codificante/genética , Animais , Autopsia , Estudos de Casos e Controles , Aberrações Cromossômicas , Cromossomos Humanos Par 15/genética , Éxons/genética , Lobo Frontal/metabolismo , Humanos , Deficiência Intelectual/genética , Neurônios/metabolismo , Primatas/genética , Fatores de Transcrição SOXD/metabolismo , Especificidade da Espécie , Lobo Temporal/metabolismo , Transcriptoma/genética
12.
Am J Hum Genet ; 99(3): 540-554, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27569545

RESUMO

Rare mutations, including copy-number variants (CNVs), contribute significantly to autism spectrum disorder (ASD) risk. Although their importance has been established in families with only one affected child (simplex families), the contribution of both de novo and inherited CNVs to ASD in families with multiple affected individuals (multiplex families) is less well understood. We analyzed 1,532 families from the Autism Genetic Resource Exchange (AGRE) to assess the impact of de novo and rare CNVs on ASD risk in multiplex families. We observed a higher burden of large, rare CNVs, including inherited events, in individuals with ASD than in their unaffected siblings (odds ratio [OR] = 1.7), but the rate of de novo events was significantly lower than in simplex families. In previously characterized ASD risk loci, we identified 49 CNVs, comprising 24 inherited events, 19 de novo events, and 6 events of unknown inheritance, a significant enrichment in affected versus control individuals (OR = 3.3). In 21 of the 30 families (71%) in whom at least one affected sibling harbored an established ASD major risk CNV, including five families harboring inherited CNVs, the CNV was not shared by all affected siblings, indicating that other risk factors are contributing. We also identified a rare risk locus for ASD and language delay at chromosomal region 2q24 (implicating NR4A2) and another lower-penetrance locus involving inherited deletions and duplications of WWOX. The genetic architecture in multiplex families differs from that in simplex families and is complex, warranting more complete genetic characterization of larger multiplex ASD cohorts.


Assuntos
Transtorno do Espectro Autista/genética , Variações do Número de Cópias de DNA/genética , Predisposição Genética para Doença/genética , Cromossomos Humanos Par 2/genética , Estudos de Coortes , Bases de Dados Genéticas , Éxons/genética , Feminino , Duplicação Gênica/genética , Estudo de Associação Genômica Ampla , Humanos , Transtornos do Desenvolvimento da Linguagem/genética , Masculino , Razão de Chances , Análise de Sequência com Séries de Oligonucleotídeos , Oxirredutases/genética , Penetrância , Regiões Promotoras Genéticas/genética , Fatores de Risco , Deleção de Sequência/genética , Irmãos , Proteínas Supressoras de Tumor/genética , Regiões não Traduzidas/genética , Oxidorredutase com Domínios WW
13.
Proc Natl Acad Sci U S A ; 112(38): E5308-17, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26324905

RESUMO

Prions are proteins that adopt alternative conformations that become self-propagating; the PrP(Sc) prion causes the rare human disorder Creutzfeldt-Jakob disease (CJD). We report here that multiple system atrophy (MSA) is caused by a different human prion composed of the α-synuclein protein. MSA is a slowly evolving disorder characterized by progressive loss of autonomic nervous system function and often signs of parkinsonism; the neuropathological hallmark of MSA is glial cytoplasmic inclusions consisting of filaments of α-synuclein. To determine whether human α-synuclein forms prions, we examined 14 human brain homogenates for transmission to cultured human embryonic kidney (HEK) cells expressing full-length, mutant human α-synuclein fused to yellow fluorescent protein (α-syn140*A53T-YFP) and TgM83(+/-) mice expressing α-synuclein (A53T). The TgM83(+/-) mice that were hemizygous for the mutant transgene did not develop spontaneous illness; in contrast, the TgM83(+/+) mice that were homozygous developed neurological dysfunction. Brain extracts from 14 MSA cases all transmitted neurodegeneration to TgM83(+/-) mice after incubation periods of ∼120 d, which was accompanied by deposition of α-synuclein within neuronal cell bodies and axons. All of the MSA extracts also induced aggregation of α-syn*A53T-YFP in cultured cells, whereas none of six Parkinson's disease (PD) extracts or a control sample did so. Our findings argue that MSA is caused by a unique strain of α-synuclein prions, which is different from the putative prions causing PD and from those causing spontaneous neurodegeneration in TgM83(+/+) mice. Remarkably, α-synuclein is the first new human prion to be identified, to our knowledge, since the discovery a half century ago that CJD was transmissible.


Assuntos
Atrofia de Múltiplos Sistemas/metabolismo , Transtornos Parkinsonianos/metabolismo , Príons/metabolismo , alfa-Sinucleína/metabolismo , Idoso , Animais , Encéfalo/patologia , Éxons , Feminino , Células HEK293 , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Transgênicos , Microscopia de Fluorescência , Pessoa de Meia-Idade , Atrofia de Múltiplos Sistemas/genética , Doenças Neurodegenerativas/metabolismo , Fosforilação , Polimorfismo de Nucleotídeo Único , Ubiquinona/análogos & derivados , Ubiquinona/metabolismo , alfa-Sinucleína/genética
14.
Neuron ; 87(6): 1215-1233, 2015 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-26402605

RESUMO

Analysis of de novo CNVs (dnCNVs) from the full Simons Simplex Collection (SSC) (N = 2,591 families) replicates prior findings of strong association with autism spectrum disorders (ASDs) and confirms six risk loci (1q21.1, 3q29, 7q11.23, 16p11.2, 15q11.2-13, and 22q11.2). The addition of published CNV data from the Autism Genome Project (AGP) and exome sequencing data from the SSC and the Autism Sequencing Consortium (ASC) shows that genes within small de novo deletions, but not within large dnCNVs, significantly overlap the high-effect risk genes identified by sequencing. Alternatively, large dnCNVs are found likely to contain multiple modest-effect risk genes. Overall, we find strong evidence that de novo mutations are associated with ASD apart from the risk for intellectual disability. Extending the transmission and de novo association test (TADA) to include small de novo deletions reveals 71 ASD risk loci, including 6 CNV regions (noted above) and 65 risk genes (FDR ≤ 0.1).


Assuntos
Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/genética , Loci Gênicos/genética , Variação Genética/genética , Mapas de Interação de Proteínas/genética , Feminino , Humanos , Masculino
15.
Am J Psychiatry ; 172(3): 266-75, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25727539

RESUMO

OBJECTIVE: Autism spectrum disorder is characterized by deficits in social function and the presence of repetitive and restrictive behaviors. Following a previous test of principle, the authors adopted a quantitative approach to discovering genes contributing to the broader autism phenotype by using social responsiveness as an endophenotype for autism spectrum disorder. METHOD: Linkage analyses using scores from the Social Responsiveness Scale were performed in 590 families from the Autism Genetic Resource Exchange, a largely multiplex autism spectrum disorder cohort. Regional and genomewide association analyses were performed to search for common variants contributing to social responsiveness. RESULTS: Social Responsiveness Scale scores were unimodally distributed in male offspring from multiplex autism families, in contrast with a bimodal distribution observed in female offspring. In correlated analyses differing by Social Responsiveness Scale respondent, genomewide significant linkage for social responsiveness was identified at chr8p21.3 (multipoint LOD=4.11; teacher/parent scores) and chr8q24.22 (multipoint LOD=4.54; parent-only scores), respectively. Genomewide or linkage-directed association analyses did not detect common variants contributing to social responsiveness. CONCLUSIONS: The sex-differential distributions of Social Responsiveness Scale scores in multiplex autism families likely reflect mechanisms contributing to the sex ratio for autism observed in the general population and form a quantitative signature of reduced penetrance of inherited liability to autism spectrum disorder among females. The identification of two strong loci for social responsiveness validates the endophenotype approach for the identification of genetic variants contributing to complex traits such as autism spectrum disorder. While causal mutations have yet to be identified, these findings are consistent with segregation of rare genetic variants influencing social responsiveness and underscore the increasingly recognized role of rare inherited variants in the genetic architecture of autism spectrum disorder.


Assuntos
Sintomas Comportamentais/genética , Transtornos Globais do Desenvolvimento Infantil , Cromossomos Humanos Par 8 , Inteligência Emocional/genética , Endofenótipos , Adulto , Criança , Transtornos Globais do Desenvolvimento Infantil/genética , Transtornos Globais do Desenvolvimento Infantil/psicologia , Família , Feminino , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Masculino , Distribuição por Sexo
16.
Biol Psychiatry ; 77(9): 775-84, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25534755

RESUMO

BACKGROUND: Phenotypic heterogeneity in autism has long been conjectured to be a major hindrance to the discovery of genetic risk factors, leading to numerous attempts to stratify children based on phenotype to increase power of discovery studies. This approach, however, is based on the hypothesis that phenotypic heterogeneity closely maps to genetic variation, which has not been tested. Our study examines the impact of subphenotyping of a well-characterized autism spectrum disorder (ASD) sample on genetic homogeneity and the ability to discover common genetic variants conferring liability to ASD. METHODS: Genome-wide genotypic data of 2576 families from the Simons Simplex Collection were analyzed in the overall sample and phenotypic subgroups defined on the basis of diagnosis, IQ, and symptom profiles. We conducted a family-based association study, as well as estimating heritability and evaluating allele scores for each phenotypic subgroup. RESULTS: Association analyses revealed no genome-wide significant association signal. Subphenotyping did not increase power substantially. Moreover, allele scores built from the most associated single nucleotide polymorphisms, based on the odds ratio in the full sample, predicted case status in subsets of the sample equally well and heritability estimates were very similar for all subgroups. CONCLUSIONS: In genome-wide association analysis of the Simons Simplex Collection sample, reducing phenotypic heterogeneity had at most a modest impact on genetic homogeneity. Our results are based on a relatively small sample, one with greater homogeneity than the entire population; if they apply more broadly, they imply that analysis of subphenotypes is not a productive path forward for discovering genetic risk variants in ASD.


Assuntos
Transtorno do Espectro Autista/genética , Transtorno Autístico/genética , Fenótipo , Transtorno do Espectro Autista/fisiopatologia , Transtorno do Espectro Autista/psicologia , Transtorno Autístico/fisiopatologia , Transtorno Autístico/psicologia , Família , Feminino , Predisposição Genética para Doença , Variação Genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Masculino , Polimorfismo de Nucleotídeo Único
17.
Neuron ; 83(1): 69-86, 2014 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-24991955

RESUMO

Neural stem cells have been adopted to model a wide range of neuropsychiatric conditions in vitro. However, how well such models correspond to in vivo brain has not been evaluated in an unbiased, comprehensive manner. We used transcriptomic analyses to compare in vitro systems to developing human fetal brain and observed strong conservation of in vivo gene expression and network architecture in differentiating primary human neural progenitor cells (phNPCs). Conserved modules are enriched in genes associated with ASD, supporting the utility of phNPCs for studying neuropsychiatric disease. We also developed and validated a machine learning approach called CoNTExT that identifies the developmental maturity and regional identity of in vitro models. We observed strong differences between in vitro models, including hiPSC-derived neural progenitors from multiple laboratories. This work provides a systems biology framework for evaluating in vitro systems and supports their value in studying the molecular mechanisms of human neurodevelopmental disease.


Assuntos
Inteligência Artificial , Córtex Cerebral/embriologia , Células-Tronco Embrionárias/fisiologia , Redes Reguladoras de Genes/genética , Modelos Neurológicos , Células-Tronco Neurais/fisiologia , Inteligência Artificial/tendências , Células Cultivadas , Córtex Cerebral/citologia , Feminino , Humanos , Masculino
18.
Autism Res ; 7(3): 355-62, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24821083

RESUMO

The proximal region of chromosome 15 is one of the genomic hotspots for copy number variants (CNVs). Among the rearrangements observed in this region, CNVs from the interval between the common breakpoints 1 and 2 (BP1 and BP2) have been reported cosegregating with autism spectrum disorder (ASD). Although evidence supporting an association between BP1-BP2 CNVs and autism accumulates, the magnitude of the effect of BP1-BP2 CNVs remains elusive, posing a great challenge to recurrence-risk counseling. To gain further insight into their pathogenicity for ASD, we estimated the penetrance of the BP1-BP2 CNVs for ASD as well as their effects on ASD-related phenotypes in a well-characterized ASD sample (n = 2525 families). Transmission disequilibrium test revealed significant preferential transmission only for the duplicated chromosome in probands (20T:9NT). The penetrance of the BP1-BP2 CNVs for ASD was low, conferring additional risks of 0.3% (deletion) and 0.8% (duplication). Stepwise regression analyses suggest a greater effect of the CNVs on ASD-related phenotype in males and when maternally inherited. Taken together, the results are consistent with BP1-BP2 CNVs as risk factors for autism. However, their effect is modest, more akin to that seen for common variants. To be consistent with the current American College of Medical Genetics guidelines for interpretation of postnatal CNV, the BP1-BP2 deletion and duplication CNVs would probably best be classified as variants of uncertain significance (VOUS): they appear to have an impact on risk, but one so modest that these CNVs do not merit pathogenic status.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/genética , Deleção Cromossômica , Cromossomos Humanos Par 15/genética , Variações do Número de Cópias de DNA/genética , Predisposição Genética para Doença/genética , Adulto , Criança , Feminino , Humanos , Masculino
19.
Mol Autism ; 5(1): 28, 2014 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-24720851

RESUMO

BACKGROUND: Validating the potential pathogenicity of copy number variants (CNVs) identified in genome-wide studies of autism spectrum disorders (ASD) requires detailed assessment of case/control frequencies, inheritance patterns, clinical correlations, and functional impact. Here, we characterize a small recurrent duplication in the annexin A1 (ANXA1) gene, identified by the Autism Genome Project (AGP) study. METHODS: From the AGP CNV genomic screen in 2,147 ASD individuals, we selected for characterization an ANXA1 gene duplication that was absent in 4,964 population-based controls. We further screened the duplication in a follow-up sample including 1,496 patients and 410 controls, and evaluated clinical correlations and family segregation. Sequencing of exonic/downstream ANXA1 regions was performed in 490 ASD patients for identification of additional variants. RESULTS: The ANXA1 duplication, overlapping the last four exons and 3'UTR region, had an overall prevalence of 11/3,643 (0.30%) in unrelated ASD patients but was not identified in 5,374 controls. Duplication carriers presented no distinctive clinical phenotype. Family analysis showed neuropsychiatric deficits and ASD traits in multiple relatives carrying the duplication, suggestive of a complex genetic inheritance. Sequencing of exonic regions and the 3'UTR identified 11 novel changes, but no obvious variants with clinical significance. CONCLUSIONS: We provide multilevel evidence for a role of ANXA1 in ASD etiology. Given its important role as mediator of glucocorticoid function in a wide variety of brain processes, including neuroprotection, apoptosis, and control of the neuroendocrine system, the results add ANXA1 to the growing list of rare candidate genetic etiological factors for ASD.

20.
Am J Hum Genet ; 94(5): 677-94, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24768552

RESUMO

Rare copy-number variation (CNV) is an important source of risk for autism spectrum disorders (ASDs). We analyzed 2,446 ASD-affected families and confirmed an excess of genic deletions and duplications in affected versus control groups (1.41-fold, p = 1.0 × 10(-5)) and an increase in affected subjects carrying exonic pathogenic CNVs overlapping known loci associated with dominant or X-linked ASD and intellectual disability (odds ratio = 12.62, p = 2.7 × 10(-15), ∼3% of ASD subjects). Pathogenic CNVs, often showing variable expressivity, included rare de novo and inherited events at 36 loci, implicating ASD-associated genes (CHD2, HDAC4, and GDI1) previously linked to other neurodevelopmental disorders, as well as other genes such as SETD5, MIR137, and HDAC9. Consistent with hypothesized gender-specific modulators, females with ASD were more likely to have highly penetrant CNVs (p = 0.017) and were also overrepresented among subjects with fragile X syndrome protein targets (p = 0.02). Genes affected by de novo CNVs and/or loss-of-function single-nucleotide variants converged on networks related to neuronal signaling and development, synapse function, and chromatin regulation.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/genética , Variações do Número de Cópias de DNA , Redes e Vias Metabólicas/genética , Criança , Feminino , Redes Reguladoras de Genes , Humanos , Masculino , Família Multigênica , Linhagem , Deleção de Sequência
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