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 RiscoRESUMO
Genome-wide association studies, DNA sequencing studies, and other genomic studies are finding an increasing number of genetic variants associated with clinical phenotypes that may be useful in developing diagnostic, preventive, and treatment strategies for individual patients. However, few variants have been integrated into routine clinical practice. The reasons for this are several, but two of the most significant are limited evidence about the clinical implications of the variants and a lack of a comprehensive knowledge base that captures genetic variants, their phenotypic associations, and other pertinent phenotypic information that is openly accessible to clinical groups attempting to interpret sequencing data. As the field of medicine begins to incorporate genome-scale analysis into clinical care, approaches need to be developed for collecting and characterizing data on the clinical implications of variants, developing consensus on their actionability, and making this information available for clinical use. The National Human Genome Research Institute (NHGRI) and the Wellcome Trust thus convened a workshop to consider the processes and resources needed to: (1) identify clinically valid genetic variants; (2) decide whether they are actionable and what the action should be; and (3) provide this information for clinical use. This commentary outlines the key discussion points and recommendations from the workshop.
Assuntos
Variação Genética/genética , Informática Médica/métodos , Fenótipo , Medicina de Precisão/métodos , Educação , Humanos , Disseminação de Informação/métodos , National Human Genome Research Institute (U.S.) , Medicina de Precisão/tendências , Estados UnidosRESUMO
Genomic science is increasingly central to the provision of health care. Producing and applying robust genomics knowledge is a complex endeavour in which no single individual, profession, discipline or community holds all the answers. Engagement and involvement of diverse stakeholders can support alignment of societal and scientific interests, understandings and perspectives and promises better science and fairer outcomes. In this context we argue for F.A.I.R.E.R. data and data use that is Findable, Accessible, Interoperable, Reproducible, Equitable and Responsible. Yet there is a paucity of international guidance on how to engage publics, patients and participants in genomics. To support meaningful and effective engagement and involvement we developed an Engagement Framework for involving and engaging participants, patients and publics in genomics research and health implementation. The Engagement Framework is intended to support all those working in genomics research, medicine, and healthcare to deliberatively consider approaches to participant, patient and public engagement and involvement in their work. Through a series of questions, the Engagement Framework prompts new ways of thinking about the aims and purposes of engagement, and support reflection on the strengths, limitations, likely outcomes and impacts of choosing different approaches to engagement. To guide genomics activities, we describe four themes and associated questions for deliberative reflection: (i) fairness; (ii) context; (iii) heterogeneity, and (iv) recognising tensions and conflict. The four key components in the Engagement provide a framework to assist those involved in genomics to reflect on decisions they make for their initiatives, including the strategies selected, the participant, patient and public stakeholders engaged, and the anticipated goals. The Engagement Framework is one step in an actively evolving process of building genomics research and implementation cultures which foster responsible leadership and are attentive to objectives which increase equality, diversity and inclusion in participation and outcomes.
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 UnidoRESUMO
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/genéticaRESUMO
To further investigate susceptibility loci identified by genome-wide association studies, we genotyped 5,500 SNPs across 14 associated regions in 8,000 samples from a control group and 3 diseases: type 2 diabetes (T2D), coronary artery disease (CAD) and Graves' disease. We defined, using Bayes theorem, credible sets of SNPs that were 95% likely, based on posterior probability, to contain the causal disease-associated SNPs. In 3 of the 14 regions, TCF7L2 (T2D), CTLA4 (Graves' disease) and CDKN2A-CDKN2B (T2D), much of the posterior probability rested on a single SNP, and, in 4 other regions (CDKN2A-CDKN2B (CAD) and CDKAL1, FTO and HHEX (T2D)), the 95% sets were small, thereby excluding most SNPs as potentially causal. Very few SNPs in our credible sets had annotated functions, illustrating the limitations in understanding the mechanisms underlying susceptibility to common diseases. Our results also show the value of more detailed mapping to target sequences for functional studies.
Assuntos
Doença da Artéria Coronariana/genética , Diabetes Mellitus Tipo 2/genética , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Doença de Graves/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato , Teorema de Bayes , Antígeno CTLA-4/genética , Quinase 5 Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p15/genética , Genes p16 , Proteínas de Homeodomínio/genética , Humanos , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Fatores de Transcrição/genética , tRNA MetiltransferasesRESUMO
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 , EscóciaRESUMO
To identify new susceptibility loci for psoriasis, we undertook a genome-wide association study of 594,224 SNPs in 2,622 individuals with psoriasis and 5,667 controls. We identified associations at eight previously unreported genomic loci. Seven loci harbored genes with recognized immune functions (IL28RA, REL, IFIH1, ERAP1, TRAF3IP2, NFKBIA and TYK2). These associations were replicated in 9,079 European samples (six loci with a combined P < 5 × 10â»8 and two loci with a combined P < 5 × 10â»7). We also report compelling evidence for an interaction between the HLA-C and ERAP1 loci (combined P = 6.95 × 10â»6). ERAP1 plays an important role in MHC class I peptide processing. ERAP1 variants only influenced psoriasis susceptibility in individuals carrying the HLA-C risk allele. Our findings implicate pathways that integrate epidermal barrier dysfunction with innate and adaptive immune dysregulation in psoriasis pathogenesis.
Assuntos
Aminopeptidases/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Antígenos HLA-C/genética , Psoríase/genética , Mapeamento Cromossômico , Cromossomos Humanos/genética , Cromossomos Humanos X/genética , Europa (Continente) , Variação Genética , Humanos , Complexo Principal de Histocompatibilidade/genética , Antígenos de Histocompatibilidade Menor , Polimorfismo de Nucleotídeo Único , Valores de Referência , Medição de RiscoRESUMO
Ulcerative colitis is a common form of inflammatory bowel disease with a complex etiology. As part of the Wellcome Trust Case Control Consortium 2, we performed a genome-wide association scan for ulcerative colitis in 2,361 cases and 5,417 controls. Loci showing evidence of association at P < 1 x 10(-5) were followed up by genotyping in an independent set of 2,321 cases and 4,818 controls. We find genome-wide significant evidence of association at three new loci, each containing at least one biologically relevant candidate gene, on chromosomes 20q13 (HNF4A; P = 3.2 x 10(-17)), 16q22 (CDH1 and CDH3; P = 2.8 x 10(-8)) and 7q31 (LAMB1; P = 3.0 x 10(-8)). Of note, CDH1 has recently been associated with susceptibility to colorectal cancer, an established complication of longstanding ulcerative colitis. The new associations suggest that changes in the integrity of the intestinal epithelial barrier may contribute to the pathogenesis of ulcerative colitis.
Assuntos
Caderinas/genética , Cromossomos Humanos Par 20/genética , Colite Ulcerativa/genética , Predisposição Genética para Doença , Fator 4 Nuclear de Hepatócito/genética , Laminina/genética , Antígenos CD , Estudos de Casos e Controles , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/patologia , Estudo de Associação Genômica Ampla , HumanosRESUMO
We have genotyped 14,436 nonsynonymous SNPs (nsSNPs) and 897 major histocompatibility complex (MHC) tag SNPs from 1,000 independent cases of ankylosing spondylitis (AS), autoimmune thyroid disease (AITD), multiple sclerosis (MS) and breast cancer (BC). Comparing these data against a common control dataset derived from 1,500 randomly selected healthy British individuals, we report initial association and independent replication in a North American sample of two new loci related to ankylosing spondylitis, ARTS1 and IL23R, and confirmation of the previously reported association of AITD with TSHR and FCRL3. These findings, enabled in part by increased statistical power resulting from the expansion of the control reference group to include individuals from the other disease groups, highlight notable new possibilities for autoimmune regulation and suggest that IL23R may be a common susceptibility factor for the major 'seronegative' diseases.