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2.
Nature ; 534(7605): 47-54, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-27135926

RESUMO

We analysed whole-genome sequences of 560 breast cancers to advance understanding of the driver mutations conferring clonal advantage and the mutational processes generating somatic mutations. We found that 93 protein-coding cancer genes carried probable driver mutations. Some non-coding regions exhibited high mutation frequencies, but most have distinctive structural features probably causing elevated mutation rates and do not contain driver mutations. Mutational signature analysis was extended to genome rearrangements and revealed twelve base substitution and six rearrangement signatures. Three rearrangement signatures, characterized by tandem duplications or deletions, appear associated with defective homologous-recombination-based DNA repair: one with deficient BRCA1 function, another with deficient BRCA1 or BRCA2 function, the cause of the third is unknown. This analysis of all classes of somatic mutation across exons, introns and intergenic regions highlights the repertoire of cancer genes and mutational processes operating, and progresses towards a comprehensive account of the somatic genetic basis of breast cancer.


Assuntos
Neoplasias da Mama/genética , Genoma Humano/genética , Mutação/genética , Estudos de Coortes , Análise Mutacional de DNA , Replicação do DNA/genética , DNA de Neoplasias/genética , Feminino , Genes BRCA1 , Genes BRCA2 , Genômica , Humanos , Masculino , Mutagênese , Taxa de Mutação , Oncogenes/genética , Reparo de DNA por Recombinação/genética
3.
Am J Hum Genet ; 98(6): 1092-1100, 2016 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-27236921

RESUMO

Bacteremia (bacterial bloodstream infection) is a major cause of illness and death in sub-Saharan Africa but little is known about the role of human genetics in susceptibility. We conducted a genome-wide association study of bacteremia susceptibility in more than 5,000 Kenyan children as part of the Wellcome Trust Case Control Consortium 2 (WTCCC2). Both the blood-culture-proven bacteremia case subjects and healthy infants as controls were recruited from Kilifi, on the east coast of Kenya. Streptococcus pneumoniae is the most common cause of bacteremia in Kilifi and was thus the focus of this study. We identified an association between polymorphisms in a long intergenic non-coding RNA (lincRNA) gene (AC011288.2) and pneumococcal bacteremia and replicated the results in the same population (p combined = 1.69 × 10(-9); OR = 2.47, 95% CI = 1.84-3.31). The susceptibility allele is African specific, derived rather than ancestral, and occurs at low frequency (2.7% in control subjects and 6.4% in case subjects). Our further studies showed AC011288.2 expression only in neutrophils, a cell type that is known to play a major role in pneumococcal clearance. Identification of this novel association will further focus research on the role of lincRNAs in human infectious disease.


Assuntos
Bacteriemia/genética , Pneumonia Pneumocócica/genética , Polimorfismo Genético/genética , RNA Longo não Codificante/genética , Streptococcus pneumoniae/genética , Adolescente , Bacteriemia/microbiologia , Bacteriemia/patologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudo de Associação Genômica Ampla , Humanos , Lactente , Recém-Nascido , Quênia/epidemiologia , Pneumonia Pneumocócica/microbiologia , Pneumonia Pneumocócica/patologia , Fatores de Risco
4.
Nat Methods ; 10(8): 723-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23900255

RESUMO

The International Cancer Genome Consortium (ICGC) aims to catalog genomic abnormalities in tumors from 50 different cancer types. Genome sequencing reveals hundreds to thousands of somatic mutations in each tumor but only a minority of these drive tumor progression. We present the result of discussions within the ICGC on how to address the challenge of identifying mutations that contribute to oncogenesis, tumor maintenance or response to therapy, and recommend computational techniques to annotate somatic variants and predict their impact on cancer phenotype.


Assuntos
Biologia Computacional/métodos , Genoma Humano , Neoplasias/genética , Variação Genética , Humanos , Mutação
5.
FEBS J ; 274(21): 5505-17, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17916191

RESUMO

Epidermal growth factor receptor (EGFR)-mediated signal transduction is often hyperactivated in tumour cells and therefore considered a promising target for cancer therapy. A number of computational models have been developed which describe the pathway in great detail. These models are similar in their description of the activation events. The deactivation of the EGFR signalling seems to be cell type-specific and is less understood. Deactivation via receptor internalization, feedback inhibition of son of sevenless (SOS) by double phosphorylated, extracellular signal-regulated kinase (ERKPP) or transiently activated Ras-GTPase activating protein (Ras-GAP) proteins is discussed to play a role. In this study we address the question of to what extent the effect of oncogenic perturbations on EGFR signalling depend on the specific regulation structure. This is investigated using a detailed pathway model under two regulatory modes: the negative feedback via ERKPP to SOS and feed-forward deactivation via transiently activated Ras-GAP proteins. We show that the effect of receptor overexpression differs qualitatively under both regulations. In the system with transiently activated Ras-GAP it may result in an attenuation of the ERK activation. Such a nonintuitive effect was also observed experimentally. In general we find the model with transiently activated Ras-GAP to have a higher robustness towards receptor overexpression and Ras mutations. In particular, we demonstrate that this model can compensate for these oncogenic perturbations if the regulation is strong. The negative feedback can not protect the system against Ras mutations. A general sensitivity analysis, however, shows a higher robustness of the model under negative feedback, indicating the limited significance of such analyses for the prediction of specific oncogenic perturbations.


Assuntos
Receptores ErbB/metabolismo , Mutação , Oncogenes , Transdução de Sinais/genética , Animais , Simulação por Computador , Receptores ErbB/química , Receptores ErbB/genética , Humanos , Proteínas Ativadoras de ras GTPase/química , Proteínas Ativadoras de ras GTPase/metabolismo , Proteínas ras/química , Proteínas ras/genética , Proteínas ras/metabolismo
6.
Cell Rep ; 16(7): 2032-46, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27498871

RESUMO

Disordered transcriptomes of cancer encompass direct effects of somatic mutation on transcription, coordinated secondary pathway alterations, and increased transcriptional noise. To catalog the rules governing how somatic mutation exerts direct transcriptional effects, we developed an exhaustive pipeline for analyzing RNA sequencing data, which we integrated with whole genomes from 23 breast cancers. Using X-inactivation analyses, we found that cancer cells are more transcriptionally active than intermixed stromal cells. This is especially true in estrogen receptor (ER)-negative tumors. Overall, 59% of substitutions were expressed. Nonsense mutations showed lower expression levels than expected, with patterns characteristic of nonsense-mediated decay. 14% of 4,234 rearrangements caused transcriptional abnormalities, including exon skips, exon reusage, fusions, and premature polyadenylation. We found productive, stable transcription from sense-to-antisense gene fusions and gene-to-intergenic rearrangements, suggesting that these mutation classes drive more transcriptional disruption than previously suspected. Systematic integration of transcriptome with genome data reveals the rules by which transcriptional machinery interprets somatic mutation.


Assuntos
Algoritmos , Neoplasias da Mama/genética , Exoma , Regulação Neoplásica da Expressão Gênica , Mutação , Transcriptoma , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Interpretação Estatística de Dados , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Poliadenilação , Receptores de Estrogênio/deficiência , Receptores de Estrogênio/genética , Inativação do Cromossomo X
7.
Biol Psychiatry ; 75(5): 386-97, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23871474

RESUMO

BACKGROUND: Genome-wide association studies (GWAS) have identified several loci associated with schizophrenia and/or bipolar disorder. We performed a GWAS of psychosis as a broad syndrome rather than within specific diagnostic categories. METHODS: 1239 cases with schizophrenia, schizoaffective disorder, or psychotic bipolar disorder; 857 of their unaffected relatives, and 2739 healthy controls were genotyped with the Affymetrix 6.0 single nucleotide polymorphism (SNP) array. Analyses of 695,193 SNPs were conducted using UNPHASED, which combines information across families and unrelated individuals. We attempted to replicate signals found in 23 genomic regions using existing data on nonoverlapping samples from the Psychiatric GWAS Consortium and Schizophrenia-GENE-plus cohorts (10,352 schizophrenia patients and 24,474 controls). RESULTS: No individual SNP showed compelling evidence for association with psychosis in our data. However, we observed a trend for association with same risk alleles at loci previously associated with schizophrenia (one-sided p = .003). A polygenic score analysis found that the Psychiatric GWAS Consortium's panel of SNPs associated with schizophrenia significantly predicted disease status in our sample (p = 5 × 10(-14)) and explained approximately 2% of the phenotypic variance. CONCLUSIONS: Although narrowly defined phenotypes have their advantages, we believe new loci may also be discovered through meta-analysis across broad phenotypes. The novel statistical methodology we introduced to model effect size heterogeneity between studies should help future GWAS that combine association evidence from related phenotypes. Applying these approaches, we highlight three loci that warrant further investigation. We found that SNPs conveying risk for schizophrenia are also predictive of disease status in our data.


Assuntos
Polimorfismo de Nucleotídeo Único/genética , Transtornos Psicóticos/genética , Esquizofrenia/genética , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Fenótipo , Análise de Componente Principal
8.
Nat Commun ; 5: 4204, 2014 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-25003214

RESUMO

Dissecting how genetic and environmental influences impact on learning is helpful for maximizing numeracy and literacy. Here we show, using twin and genome-wide analysis, that there is a substantial genetic component to children's ability in reading and mathematics, and estimate that around one half of the observed correlation in these traits is due to shared genetic effects (so-called Generalist Genes). Thus, our results highlight the potential role of the learning environment in contributing to differences in a child's cognitive abilities at age twelve.


Assuntos
Dislexia/genética , Genética Populacional , Matemática , Característica Quantitativa Herdável , Leitura , Gêmeos/genética , Criança , Dislexia/psicologia , Feminino , Estudo de Associação Genômica Ampla , Humanos , Aprendizagem , Masculino , Polimorfismo de Nucleotídeo Único , Gêmeos/psicologia , Reino Unido
9.
Nat Genet ; 45(2): 208-13, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23291585

RESUMO

To identify susceptibility loci for visceral leishmaniasis, we undertook genome-wide association studies in two populations: 989 cases and 1,089 controls from India and 357 cases in 308 Brazilian families (1,970 individuals). The HLA-DRB1-HLA-DQA1 locus was the only region to show strong evidence of association in both populations. Replication at this region was undertaken in a second Indian population comprising 941 cases and 990 controls, and combined analysis across the three cohorts for rs9271858 at this locus showed P(combined) = 2.76 × 10(-17) and odds ratio (OR) = 1.41, 95% confidence interval (CI) = 1.30-1.52. A conditional analysis provided evidence for multiple associations within the HLA-DRB1-HLA-DQA1 region, and a model in which risk differed between three groups of haplotypes better explained the signal and was significant in the Indian discovery and replication cohorts. In conclusion, the HLA-DRB1-HLA-DQA1 HLA class II region contributes to visceral leishmaniasis susceptibility in India and Brazil, suggesting shared genetic risk factors for visceral leishmaniasis that cross the epidemiological divides of geography and parasite species.


Assuntos
Predisposição Genética para Doença/genética , Cadeias alfa de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Leishmaniose Visceral/genética , Brasil , Eletroforese em Gel de Ágar , Frequência do Gene , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos/genética , Humanos , Índia , Modelos Lineares , Razão de Chances , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único/genética
10.
Nat Genet ; 44(3): 328-33, 2012 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-22306652

RESUMO

Genetic factors have been implicated in stroke risk, but few replicated associations have been reported. We conducted a genome-wide association study (GWAS) for ischemic stroke and its subtypes in 3,548 affected individuals and 5,972 controls, all of European ancestry. Replication of potential signals was performed in 5,859 affected individuals and 6,281 controls. We replicated previous associations for cardioembolic stroke near PITX2 and ZFHX3 and for large vessel stroke at a 9p21 locus. We identified a new association for large vessel stroke within HDAC9 (encoding histone deacetylase 9) on chromosome 7p21.1 (including further replication in an additional 735 affected individuals and 28,583 controls) (rs11984041; combined P = 1.87 × 10(-11); odds ratio (OR) = 1.42, 95% confidence interval (CI) = 1.28-1.57). All four loci exhibited evidence for heterogeneity of effect across the stroke subtypes, with some and possibly all affecting risk for only one subtype. This suggests distinct genetic architectures for different stroke subtypes.


Assuntos
Cromossomos Humanos Par 7/genética , Predisposição Genética para Doença/genética , Histona Desacetilases/genética , Proteínas Repressoras/genética , Acidente Vascular Cerebral/genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética
11.
Nat Genet ; 43(2): 117-20, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21186350

RESUMO

Metformin is the most commonly used pharmacological therapy for type 2 diabetes. We report a genome-wide association study for glycemic response to metformin in 1,024 Scottish individuals with type 2 diabetes with replication in two cohorts including 1,783 Scottish individuals and 1,113 individuals from the UK Prospective Diabetes Study. In a combined meta-analysis, we identified a SNP, rs11212617, associated with treatment success (n = 3,920, P = 2.9 × 10(-9), odds ratio = 1.35, 95% CI 1.22-1.49) at a locus containing ATM, the ataxia telangiectasia mutated gene. In a rat hepatoma cell line, inhibition of ATM with KU-55933 attenuated the phosphorylation and activation of AMP-activated protein kinase in response to metformin. We conclude that ATM, a gene known to be involved in DNA repair and cell cycle control, plays a role in the effect of metformin upstream of AMP-activated protein kinase, and variation in this gene alters glycemic response to metformin.


Assuntos
Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA/genética , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Metformina/farmacologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Supressoras de Tumor/genética , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Relação Dose-Resposta a Droga , Estudo de Associação Genômica Ampla , Humanos , Hipoglicemiantes/farmacologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Polimorfismo de Nucleotídeo Único , Proteínas Quinases/metabolismo , Ratos , Escócia
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