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The identification of subjects at high risk for Alzheimer's disease is important for prognosis and early intervention. We investigated the polygenic architecture of Alzheimer's disease and the accuracy of Alzheimer's disease prediction models, including and excluding the polygenic component in the model. This study used genotype data from the powerful dataset comprising 17 008 cases and 37 154 controls obtained from the International Genomics of Alzheimer's Project (IGAP). Polygenic score analysis tested whether the alleles identified to associate with disease in one sample set were significantly enriched in the cases relative to the controls in an independent sample. The disease prediction accuracy was investigated in a subset of the IGAP data, a sample of 3049 cases and 1554 controls (for whom APOE genotype data were available) by means of sensitivity, specificity, area under the receiver operating characteristic curve (AUC) and positive and negative predictive values. We observed significant evidence for a polygenic component enriched in Alzheimer's disease (P = 4.9 × 10(-26)). This enrichment remained significant after APOE and other genome-wide associated regions were excluded (P = 3.4 × 10(-19)). The best prediction accuracy AUC = 78.2% (95% confidence interval 77-80%) was achieved by a logistic regression model with APOE, the polygenic score, sex and age as predictors. In conclusion, Alzheimer's disease has a significant polygenic component, which has predictive utility for Alzheimer's disease risk and could be a valuable research tool complementing experimental designs, including preventative clinical trials, stem cell selection and high/low risk clinical studies. In modelling a range of sample disease prevalences, we found that polygenic scores almost doubles case prediction from chance with increased prediction at polygenic extremes.
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Doença de Alzheimer/genética , Predisposição Genética para Doença/genética , Variação Genética/genética , Herança Multifatorial/genética , Alelos , Apolipoproteínas E/genética , Estudos de Casos e Controles , Testes Genéticos , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Modelos Logísticos , Curva ROC , RiscoRESUMO
The role of superoxide dismutases (SODs) in aging and oxidative stress regulation has been widely studied and there is growing evidence that imbalances in these processes influence lifespan in several species. In humans, genetic polymorphisms in SOD genes may play an important role in the development of age-related diseases and genetic variation in SOD2 is thought to be associated with longevity. These observations prompted us to perform a case-control association study using a comprehensive haplotype tagging approach for the three SOD genes (SOD1, SOD2, SOD3) by testing a total of 19 SNPs in our extensive collection of 1,612 long-lived individuals (centenarians and nonagenarians) and 1,104 younger controls. Furthermore, we intended to replicate the previous association of the SOD2 SNP rs4880 with longevity observed in a Danish cohort. In our study, no association was detected between the tested SNPs and the longevity phenotype, neither in the entire long-lived sample set nor in the centenarian subgroup analysis. Our results suggest that there is no considerable influence of sequence variation in the SOD genes on human longevity in Germans.
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Longevidade/genética , Polimorfismo de Nucleotídeo Único , Superóxido Dismutase/genética , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Frequência do Gene , Alemanha , Haplótipos , Humanos , Masculino , Fenótipo , Superóxido Dismutase-1RESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Risk for late-onset Alzheimer's disease (LOAD), the most prevalent dementia, is partially driven by genetics. To identify LOAD risk loci, we performed a large genome-wide association meta-analysis of clinically diagnosed LOAD (94,437 individuals). We confirm 20 previous LOAD risk loci and identify five new genome-wide loci (IQCK, ACE, ADAM10, ADAMTS1, and WWOX), two of which (ADAM10, ACE) were identified in a recent genome-wide association (GWAS)-by-familial-proxy of Alzheimer's or dementia. Fine-mapping of the human leukocyte antigen (HLA) region confirms the neurological and immune-mediated disease haplotype HLA-DR15 as a risk factor for LOAD. Pathway analysis implicates immunity, lipid metabolism, tau binding proteins, and amyloid precursor protein (APP) metabolism, showing that genetic variants affecting APP and Aß processing are associated not only with early-onset autosomal dominant Alzheimer's disease but also with LOAD. Analyses of risk genes and pathways show enrichment for rare variants (P = 1.32 × 10-7), indicating that additional rare variants remain to be identified. We also identify important genetic correlations between LOAD and traits such as family history of dementia and education.
Assuntos
Doença de Alzheimer/genética , Peptídeos beta-Amiloides/genética , Loci Gênicos/genética , Predisposição Genética para Doença/genética , Imunidade/genética , Lipídeos/genética , Proteínas tau/genética , Idoso , Estudos de Casos e Controles , Feminino , Testes Genéticos/métodos , Estudo de Associação Genômica Ampla/métodos , Haplótipos/genética , Humanos , Metabolismo dos Lipídeos/genética , MasculinoRESUMO
The original version of this Article contained an error in the spelling of the author Robert Häsler, which was incorrectly given as Robert Häesler. This has now been corrected in both the PDF and HTML versions of the Article.
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FOXO3 is consistently annotated as a human longevity gene. However, functional variants and underlying mechanisms for the association remain unknown. Here, we perform resequencing of the FOXO3 locus and single-nucleotide variant (SNV) genotyping in three European populations. We find two FOXO3 SNVs, rs12206094 and rs4946935, to be most significantly associated with longevity and further characterize them functionally. We experimentally validate the in silico predicted allele-dependent binding of transcription factors (CTCF, SRF) to the SNVs. Specifically, in luciferase reporter assays, the longevity alleles of both variants show considerable enhancer activities that are reversed by IGF-1 treatment. An eQTL database search reveals that the alleles are also associated with higher FOXO3 mRNA expression in various human tissues, which is in line with observations in long-lived model organisms. In summary, we present experimental evidence for a functional link between common intronic variants in FOXO3 and human longevity.
Assuntos
Proteína Forkhead Box O3/fisiologia , Longevidade/genética , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Alelos , Fator de Ligação a CCCTC/genética , Fator de Ligação a CCCTC/metabolismo , Simulação por Computador , Feminino , Proteína Forkhead Box O3/genética , Haplótipos/genética , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Íntrons/genética , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Fator de Resposta Sérica/genética , Fator de Resposta Sérica/metabolismoRESUMO
We identified rare coding variants associated with Alzheimer's disease in a three-stage case-control study of 85,133 subjects. In stage 1, we genotyped 34,174 samples using a whole-exome microarray. In stage 2, we tested associated variants (P < 1 × 10-4) in 35,962 independent samples using de novo genotyping and imputed genotypes. In stage 3, we used an additional 14,997 samples to test the most significant stage 2 associations (P < 5 × 10-8) using imputed genotypes. We observed three new genome-wide significant nonsynonymous variants associated with Alzheimer's disease: a protective variant in PLCG2 (rs72824905: p.Pro522Arg, P = 5.38 × 10-10, odds ratio (OR) = 0.68, minor allele frequency (MAF)cases = 0.0059, MAFcontrols = 0.0093), a risk variant in ABI3 (rs616338: p.Ser209Phe, P = 4.56 × 10-10, OR = 1.43, MAFcases = 0.011, MAFcontrols = 0.008), and a new genome-wide significant variant in TREM2 (rs143332484: p.Arg62His, P = 1.55 × 10-14, OR = 1.67, MAFcases = 0.0143, MAFcontrols = 0.0089), a known susceptibility gene for Alzheimer's disease. These protein-altering changes are in genes highly expressed in microglia and highlight an immune-related protein-protein interaction network enriched for previously identified risk genes in Alzheimer's disease. These genetic findings provide additional evidence that the microglia-mediated innate immune response contributes directly to the development of Alzheimer's disease.
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Proteínas Adaptadoras de Transdução de Sinal/genética , Doença de Alzheimer/genética , Imunidade Inata/genética , Glicoproteínas de Membrana/genética , Microglia/metabolismo , Fosfolipase C gama/genética , Polimorfismo de Nucleotídeo Único , Receptores Imunológicos/genética , Sequência de Aminoácidos , Estudos de Casos e Controles , Exoma/genética , Perfilação da Expressão Gênica , Frequência do Gene , Predisposição Genética para Doença/genética , Genótipo , Humanos , Desequilíbrio de Ligação , Razão de Chances , Mapas de Interação de Proteínas/genética , Homologia de Sequência de AminoácidosRESUMO
TCF3-HLF-positive acute lymphoblastic leukemia (ALL) is currently incurable. Using an integrated approach, we uncovered distinct mutation, gene expression and drug response profiles in TCF3-HLF-positive and treatment-responsive TCF3-PBX1-positive ALL. We identified recurrent intragenic deletions of PAX5 or VPREB1 in constellation with the fusion of TCF3 and HLF. Moreover somatic mutations in the non-translocated allele of TCF3 and a reduction of PAX5 gene dosage in TCF3-HLF ALL suggest cooperation within a restricted genetic context. The enrichment for stem cell and myeloid features in the TCF3-HLF signature may reflect reprogramming by TCF3-HLF of a lymphoid-committed cell of origin toward a hybrid, drug-resistant hematopoietic state. Drug response profiling of matched patient-derived xenografts revealed a distinct profile for TCF3-HLF ALL with resistance to conventional chemotherapeutics but sensitivity to glucocorticoids, anthracyclines and agents in clinical development. Striking on-target sensitivity was achieved with the BCL2-specific inhibitor venetoclax (ABT-199). This integrated approach thus provides alternative treatment options for this deadly disease.