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1.
Int J Cancer ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31732966

RESUMO

In prostate adenocarcinoma (PCa), distinction between indolent and aggressive disease is challenging. Around 50% of PCa are characterized by TMPRSS2-ERG (T2E)-fusion oncoproteins defining two molecular subtypes (T2E-positive/negative). However, current prognostic tests do not differ between both molecular subtypes, which might affect outcome prediction. To investigate gene-signatures associated with metastasis in T2E-positive and T2E-negative PCa independently, we integrated tumor transcriptomes and clinicopathological data of two cohorts (total n = 783), and analyzed metastasis-associated gene-signatures regarding the T2E-status. Here, we show that the prognostic value of biomarkers in PCa critically depends on the T2E-status. Using gene-set enrichment analyses, we uncovered that metastatic T2E-positive and T2E-negative PCa are characterized by distinct gene-signatures. In addition, by testing genes shared by several functional gene-signatures for their association with event-free survival in a validation cohort (n = 272), we identified five genes (ASPN, BGN, COL1A1, RRM2 and TYMS)-three of which are included in commercially available prognostic tests-whose high expression was significantly associated with worse outcome exclusively in T2E-negative PCa. Among these genes, RRM2 and TYMS were validated by immunohistochemistry in another validation cohort (n = 135), and several of them proved to add prognostic information to current clinicopathological predictors, such as Gleason score, exclusively for T2E-negative patients. No prognostic biomarkers were identified exclusively for T2E-positive tumors. Collectively, our study discovers that the T2E-status, which is per se not a strong prognostic biomarker, crucially determines the prognostic value of other biomarkers. Our data suggest that the molecular subtype needs to be considered when applying prognostic biomarkers for outcome prediction in PCa.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31707051

RESUMO

BACKGROUND: 15% of atopic dermatitis liability-scale heritability could be attributed to 31 susceptibility loci identified by genome-wide association studies, with only three of them (IL13, IL6R, and FLG) resolved to protein-coding variants. OBJECTIVE: We examined whether a significant portion of unexplained atopic dermatitis heritability is further explained by low-frequency and rare variants in gene coding sequence. METHODS: We evaluated common, low-frequency and rare protein-coding variants using exome chip and replication genotype data of 15,574 patients and 377,839 controls, combined with whole transcriptome data on lesional, non-lesional and healthy skin samples of 27 patients and 38 controls. RESULTS: Additional 12.56% (s.e. 0.74%) of atopic dermatitis heritability is explained by rare protein-coding variation. We identified Docking protein 2 (DOK2) and CD200 Receptor 1 (CD200R1) as novel genome-wide significant susceptibility genes. Rare coding variants associated with atopic dermatitis are further enriched in five genes (IL4R, IL13, JAK1, JAK2, TYK2) of the IL13 pathway, all of which are targets for novel systemic atopic dermatitis therapeutics. Multiomics-based network and RNA-Sequencing analysis revealed DOK2 as a central hub interacting, among others, with CD200R1, IL6R and STAT3. Multi-tissue gene expression profile analysis for 53 tissue types from GTEx showed that disease-associated protein-coding variants exert their greatest effect in skin tissues. CONCLUSION: Our discoveries highlight a major role of rare coding variants in atopic dermatitis acting independently of common variants. Further extensive functional studies are required to detect all potential causal variants and to specify the contribution of novel susceptibility genes DOK2 and CD200R1 to overall disease susceptibility.

3.
Sci Rep ; 9(1): 9439, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31263163

RESUMO

Type 2 diabetes (T2D) affects the health of millions of people worldwide. The identification of genetic determinants associated with changes in glycemia over time might illuminate biological features that precede the development of T2D. Here we conducted a genome-wide association study of longitudinal fasting glucose changes in up to 13,807 non-diabetic individuals of European descent from nine cohorts. Fasting glucose change over time was defined as the slope of the line defined by multiple fasting glucose measurements obtained over up to 14 years of observation. We tested for associations of genetic variants with inverse-normal transformed fasting glucose change over time adjusting for age at baseline, sex, and principal components of genetic variation. We found no genome-wide significant association (P < 5 × 10-8) with fasting glucose change over time. Seven loci previously associated with T2D, fasting glucose or HbA1c were nominally (P < 0.05) associated with fasting glucose change over time. Limited power influences unambiguous interpretation, but these data suggest that genetic effects on fasting glucose change over time are likely to be small. A public version of the data provides a genomic resource to combine with future studies to evaluate shared genetic links with T2D and other metabolic risk traits.

4.
J Am Coll Cardiol ; 73(24): 3118-3131, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31221261

RESUMO

BACKGROUND: Subclinical changes on the electrocardiogram are risk factors for cardiovascular mortality. Recognition and knowledge of electrolyte associations in cardiac electrophysiology are based on only in vitro models and observations in patients with severe medical conditions. OBJECTIVES: This study sought to investigate associations between serum electrolyte concentrations and changes in cardiac electrophysiology in the general population. METHODS: Summary results collected from 153,014 individuals (54.4% women; mean age 55.1 ± 12.1 years) from 33 studies (of 5 ancestries) were meta-analyzed. Linear regression analyses examining associations between electrolyte concentrations (mmol/l of calcium, potassium, sodium, and magnesium), and electrocardiographic intervals (RR, QT, QRS, JT, and PR intervals) were performed. The study adjusted for potential confounders and also stratified by ancestry, sex, and use of antihypertensive drugs. RESULTS: Lower calcium was associated with longer QT intervals (-11.5 ms; 99.75% confidence interval [CI]: -13.7 to -9.3) and JT duration, with sex-specific effects. In contrast, higher magnesium was associated with longer QT intervals (7.2 ms; 99.75% CI: 1.3 to 13.1) and JT. Lower potassium was associated with longer QT intervals (-2.8 ms; 99.75% CI: -3.5 to -2.0), JT, QRS, and PR durations, but all potassium associations were driven by use of antihypertensive drugs. No physiologically relevant associations were observed for sodium or RR intervals. CONCLUSIONS: The study identified physiologically relevant associations between electrolytes and electrocardiographic intervals in a large-scale analysis combining cohorts from different settings. The results provide insights for further cardiac electrophysiology research and could potentially influence clinical practice, especially the association between calcium and QT duration, by which calcium levels at the bottom 2% of the population distribution led to clinically relevant QT prolongation by >5 ms.

5.
Eur J Hum Genet ; 27(6): 952-962, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30679814

RESUMO

Genome-wide association studies (GWAS) of quantitative electrocardiographic (ECG) traits in large consortia have identified more than 130 loci associated with QT interval, QRS duration, PR interval, and heart rate (RR interval). In the current study, we meta-analyzed genome-wide association results from 30,000 mostly Dutch samples on four ECG traits: PR interval, QRS duration, QT interval, and RR interval. SNP genotype data was imputed using the Genome of the Netherlands reference panel encompassing 19 million SNPs, including millions of rare SNPs (minor allele frequency < 5%). In addition to many known loci, we identified seven novel locus-trait associations: KCND3, NR3C1, and PLN for PR interval, KCNE1, SGIP1, and NFKB1 for QT interval, and ATP2A2 for QRS duration, of which six were successfully replicated. At these seven loci, we performed conditional analyses and annotated significant SNPs (in exons and regulatory regions), demonstrating involvement of cardiac-related pathways and regulation of nearby genes.

6.
Nat Commun ; 9(1): 4919, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30464216

RESUMO

Testing for association between a set of genetic markers and a phenotype is a fundamental task in genetic studies. Standard approaches for heritability and set testing strongly rely on parametric models that make specific assumptions regarding phenotypic variability. Here, we show that resulting p-values may be inflated by up to 15 orders of magnitude, in a heritability study of methylation measurements, and in a heritability and expression quantitative trait loci analysis of gene expression profiles. We propose FEATHER, a method for fast permutation-based testing of marker sets and of heritability, which properly controls for false-positive results. FEATHER eliminated 47% of methylation sites found to be heritable by the parametric test, suggesting a substantial inflation of false-positive findings by alternative methods. Our approach can rapidly identify heritable phenotypes out of millions of phenotypes acquired via high-throughput technologies, does not suffer from model misspecification and is highly efficient.


Assuntos
Técnicas Genéticas , Característica Quantitativa Herdável , Estatística como Assunto , Metilação de DNA , Expressão Gênica , Fenótipo
7.
PLoS One ; 13(11): e0206554, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30383853

RESUMO

BACKGROUND AND PURPOSE: Polymorphisms in coagulation genes have been associated with early-onset ischemic stroke. Here we pursue an a priori hypothesis that genetic variation in the endothelial-based receptors of the thrombomodulin-protein C system (THBD and PROCR) may similarly be associated with early-onset ischemic stroke. We explored this hypothesis utilizing a multi-stage design of discovery and replication. METHODS: Discovery was performed in the Genetics-of-Early-Onset Stroke (GEOS) Study, a biracial population-based case-control study of ischemic stroke among men and women aged 15-49 including 829 cases of first ischemic stroke (42.2% African-American) and 850 age-comparable stroke-free controls (38.1% African-American). Twenty-four single-nucleotide-polymorphisms (SNPs) in THBD and 22 SNPs in PROCR were evaluated. Following LD pruning (r2≥0.8), we advanced uncorrelated SNPs forward for association analyses. Associated SNPs were evaluated for replication in an early-onset ischemic stroke population (onset-age<60 years) consisting of 3676 cases and 21118 non-stroke controls from 6 case-control studies. Lastly, we determined if the replicated SNPs also associated with older-onset ischemic stroke in the METASTROKE data-base. RESULTS: Among GEOS Caucasians, PROCR rs9574, which was in strong LD with 8 other SNPs, and one additional independent SNP rs2069951, were significantly associated with ischemic stroke (rs9574, OR = 1.33, p = 0.003; rs2069951, OR = 1.80, p = 0.006) using an additive-model adjusting for age, gender and population-structure. Adjusting for risk factors did not change the associations; however, associations were strengthened among those without risk factors. PROCR rs9574 also associated with early-onset ischemic stroke in the replication sample (OR = 1.08, p = 0.015), but not older-onset stroke. There were no PROCR associations in African-Americans, nor were there any THBD associations in either ethnicity. CONCLUSION: PROCR polymorphisms are associated with early-onset ischemic stroke in Caucasians.


Assuntos
Isquemia Encefálica/genética , Receptor de Proteína C Endotelial/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Acidente Vascular Cerebral/genética , Trombomodulina/genética , Adolescente , Adulto , Afro-Americanos/genética , Idade de Início , Isquemia Encefálica/epidemiologia , Estudos de Casos e Controles , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/epidemiologia , Adulto Jovem
8.
Nat Commun ; 9(1): 3738, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-30218040

RESUMO

X-chromosome inactivation (XCI), i.e., the inactivation of one of the female X chromosomes, restores equal expression of X-chromosomal genes between females and males. However, ~10% of genes show variable degrees of escape from XCI between females, although little is known about the causes of variable XCI. Using a discovery data-set of 1867 females and 1398 males and a replication sample of 3351 females, we show that genetic variation at three autosomal loci is associated with female-specific changes in X-chromosome methylation. Through cis-eQTL expression analysis, we map these loci to the genes SMCHD1/METTL4, TRIM6/HBG2, and ZSCAN9. Low-expression alleles of the loci are predominantly associated with mild hypomethylation of CpG islands near genes known to variably escape XCI, implicating the autosomal genes in variable XCI. Together, these results suggest a genetic basis for variable escape from XCI and highlight the potential of a population genomics approach to identify genes involved in XCI.


Assuntos
Metilação de DNA/genética , Inativação do Cromossomo X/genética , Proteínas Cromossômicas não Histona/genética , Ilhas de CpG , Proteínas de Ligação a DNA/genética , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Variação Genética , Humanos , Masculino , Metiltransferases/genética , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/genética , gama-Globinas/genética
9.
Eur Heart J ; 39(44): 3961-3969, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30169657

RESUMO

Aims: Sudden cardiac arrest (SCA) accounts for 10% of adult mortality in Western populations. We aim to identify potential loci associated with SCA and to identify risk factors causally associated with SCA. Methods and results: We carried out a large genome-wide association study (GWAS) for SCA (n = 3939 cases, 25 989 non-cases) to examine common variation genome-wide and in candidate arrhythmia genes. We also exploited Mendelian randomization (MR) methods using cross-trait multi-variant genetic risk score associations (GRSA) to assess causal relationships of 18 risk factors with SCA. No variants were associated with SCA at genome-wide significance, nor were common variants in candidate arrhythmia genes associated with SCA at nominal significance. Using cross-trait GRSA, we established genetic correlation between SCA and (i) coronary artery disease (CAD) and traditional CAD risk factors (blood pressure, lipids, and diabetes), (ii) height and BMI, and (iii) electrical instability traits (QT and atrial fibrillation), suggesting aetiologic roles for these traits in SCA risk. Conclusions: Our findings show that a comprehensive approach to the genetic architecture of SCA can shed light on the determinants of a complex life-threatening condition with multiple influencing factors in the general population. The results of this genetic analysis, both positive and negative findings, have implications for evaluating the genetic architecture of patients with a family history of SCA, and for efforts to prevent SCA in high-risk populations and the general community.


Assuntos
Arritmias Cardíacas/genética , Morte Súbita Cardíaca/etiologia , Arritmias Cardíacas/fisiopatologia , Índice de Massa Corporal , Doença da Artéria Coronariana/genética , Feminino , Estudo de Associação Genômica Ampla , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Medição de Risco/métodos , Fatores de Risco , Fatores Sexuais
10.
Eur Heart J ; 39(45): 4020-4029, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30085086

RESUMO

Aims: Risks of catheter ablation for atrial fibrillation and flutter assessed in retrospective studies, registries, and controlled trials may underestimate 'real world' conditions. Methods and results: To assess complications in a nationwide approach, we included all cases undergoing catheter ablation for atrial fibrillation and atrial flutter in Germany in 2014, using ICD-10-GM-based German Diagnosis Related Group (G-DRG) codes and the well differentiated German Operation and Procedure Classification (OPS) analysing 33 353 in-hospital cases. For left atrial ablations (19 514 cases), the overall complication rate ranged from a mean of 11.7% to 13.8% depending on type and site of applied energy, including major complications ranging from 3.8% to 7.2%. Whereas overall complication rates were lower for atrial flutter ablations (13 871 cases, 10.5%; P < 0.001), interestingly, major complications occurred more frequently (7.4%; P < 0.001). Particularly, in-hospital death was four-times more common following right than following left atrial ablations (47 vs. 18 cases, 0.34% vs. 0.09%; P < 0.001). Stratified by centre ablation volume, significantly fewer overall complications occurred in centres performing >100 vs. ≤100 left atrial ablations annually (12.7% vs. 16.4%; P < 0.002). Conclusion: Administrative data of all atrial fibrillation ablations in Germany in 2014 revealed higher overall and major complication rates than previously reported. Few patients were treated in low volume centres, but were exposed to a higher overall complication risk. Atrial flutter ablations were associated with surprisingly high rates of life-threatening complications. Advanced age combined with highly prevalent cardiac, pulmonary and, vascular comorbidities likely play a major role. In addition, individual-level clinical studies need to address the safety and benefits of catheter ablation in an elderly, diseased population.


Assuntos
Fibrilação Atrial/cirurgia , Flutter Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade
11.
Nat Commun ; 9(1): 2904, 2018 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-30046033

RESUMO

Electrocardiographic PR interval measures atrio-ventricular depolarization and conduction, and abnormal PR interval is a risk factor for atrial fibrillation and heart block. Our genome-wide association study of over 92,000 European-descent individuals identifies 44 PR interval loci (34 novel). Examination of these loci reveals known and previously not-yet-reported biological processes involved in cardiac atrial electrical activity. Genes in these loci are over-represented in cardiac disease processes including heart block and atrial fibrillation. Variants in over half of the 44 loci were associated with atrial or blood transcript expression levels, or were in high linkage disequilibrium with missense variants. Six additional loci were identified either by meta-analysis of ~105,000 African and European-descent individuals and/or by pleiotropic analyses combining PR interval with heart rate, QRS interval, and atrial fibrillation. These findings implicate developmental pathways, and identify transcription factors, ion-channel genes, and cell-junction/cell-signaling proteins in atrio-ventricular conduction, identifying potential targets for drug development.


Assuntos
Função Atrial/fisiologia , Nó Atrioventricular/fisiologia , Fenômenos Eletrofisiológicos/genética , Estudo de Associação Genômica Ampla , Eletrocardiografia , Feminino , Humanos , Desequilíbrio de Ligação/genética , Masculino , Mutação de Sentido Incorreto/genética , Fatores de Risco
12.
Genome Biol ; 19(1): 87, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-30012220

RESUMO

BACKGROUND: Genome-wide association studies conducted on QRS duration, an electrocardiographic measurement associated with heart failure and sudden cardiac death, have led to novel biological insights into cardiac function. However, the variants identified fall predominantly in non-coding regions and their underlying mechanisms remain unclear. RESULTS: Here, we identify putative functional coding variation associated with changes in the QRS interval duration by combining Illumina HumanExome BeadChip genotype data from 77,898 participants of European ancestry and 7695 of African descent in our discovery cohort, followed by replication in 111,874 individuals of European ancestry from the UK Biobank and deCODE cohorts. We identify ten novel loci, seven within coding regions, including ADAMTS6, significantly associated with QRS duration in gene-based analyses. ADAMTS6 encodes a secreted metalloprotease of currently unknown function. In vitro validation analysis shows that the QRS-associated variants lead to impaired ADAMTS6 secretion and loss-of function analysis in mice demonstrates a previously unappreciated role for ADAMTS6 in connexin 43 gap junction expression, which is essential for myocardial conduction. CONCLUSIONS: Our approach identifies novel coding and non-coding variants underlying ventricular depolarization and provides a possible mechanism for the ADAMTS6-associated conduction changes.


Assuntos
Proteínas ADAMTS/genética , Conexina 43/genética , Exoma , Loci Gênicos , Sistema de Condução Cardíaco/metabolismo , Miocárdio/metabolismo , Grupo com Ancestrais do Continente Africano , Animais , Eletrocardiografia , Grupo com Ancestrais do Continente Europeu , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Miocárdio/patologia , Fases de Leitura Aberta , Polimorfismo de Nucleotídeo Único , Sequenciamento Completo do Exoma
13.
Circ Genom Precis Med ; 11(1): e001758, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29874175

RESUMO

BACKGROUND: QT interval, measured through a standard ECG, captures the time it takes for the cardiac ventricles to depolarize and repolarize. JT interval is the component of the QT interval that reflects ventricular repolarization alone. Prolonged QT interval has been linked to higher risk of sudden cardiac arrest. METHODS AND RESULTS: We performed an ExomeChip-wide analysis for both QT and JT intervals, including 209 449 variants, both common and rare, in 17 341 genes from the Illumina Infinium HumanExome BeadChip. We identified 10 loci that modulate QT and JT interval duration that have not been previously reported in the literature using single-variant statistical models in a meta-analysis of 95 626 individuals from 23 cohorts (comprised 83 884 European ancestry individuals, 9610 blacks, 1382 Hispanics, and 750 Asians). This brings the total number of ventricular repolarization associated loci to 45. In addition, our approach of using coding variants has highlighted the role of 17 specific genes for involvement in ventricular repolarization, 7 of which are in novel loci. CONCLUSIONS: Our analyses show a role for myocyte internal structure and interconnections in modulating QT interval duration, adding to previous known roles of potassium, sodium, and calcium ion regulation, as well as autonomic control. We anticipate that these discoveries will open new paths to the goal of making novel remedies for the prevention of lethal ventricular arrhythmias and sudden cardiac arrest.


Assuntos
Exoma/genética , Síndrome do QT Longo/diagnóstico , Locos de Características Quantitativas , Antiporters/genética , Proteínas de Ligação a DNA/genética , Eletrocardiografia , Estudo de Associação Genômica Ampla , Humanos , Síndrome do QT Longo/etnologia , Síndrome do QT Longo/genética , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Receptores de Detecção de Cálcio/genética , Fatores de Transcrição/genética
14.
Circ Genom Precis Med ; 11(5): e002037, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29748316

RESUMO

BACKGROUND: Electrical conduction from the cardiac sinoatrial node to the ventricles is critical for normal heart function. Genome-wide association studies have identified more than a dozen common genetic loci that are associated with PR interval. However, it is unclear whether rare and low-frequency variants also contribute to PR interval heritability. METHODS: We performed large-scale meta-analyses of the PR interval that included 83 367 participants of European ancestry and 9436 of African ancestry. We examined both common and rare variants associated with the PR interval. RESULTS: We identified 31 genetic loci that were significantly associated with PR interval after Bonferroni correction (P<1.2×10-6), including 11 novel loci that have not been reported previously. Many of these loci are involved in heart morphogenesis. In gene-based analysis, we found that multiple rare variants at MYH6 (P=5.9×10-11) and SCN5A (P=1.1×10-7) were associated with PR interval. SCN5A locus also was implicated in the common variant analysis, whereas MYH6 was a novel locus. CONCLUSIONS: We identified common variants at 11 novel loci and rare variants within 2 gene regions that were significantly associated with PR interval. Our findings provide novel insights to the current understanding of atrioventricular conduction, which is critical for cardiac activity and an important determinant of health.


Assuntos
Eletrocardiografia , Variação Genética , Adulto , Idoso , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Locos de Características Quantitativas/genética , Sequências Reguladoras de Ácido Nucleico/genética
15.
Nat Genet ; 50(4): 559-571, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29632382

RESUMO

We aggregated coding variant data for 81,412 type 2 diabetes cases and 370,832 controls of diverse ancestry, identifying 40 coding variant association signals (P < 2.2 × 10-7); of these, 16 map outside known risk-associated loci. We make two important observations. First, only five of these signals are driven by low-frequency variants: even for these, effect sizes are modest (odds ratio ≤1.29). Second, when we used large-scale genome-wide association data to fine-map the associated variants in their regional context, accounting for the global enrichment of complex trait associations in coding sequence, compelling evidence for coding variant causality was obtained for only 16 signals. At 13 others, the associated coding variants clearly represent 'false leads' with potential to generate erroneous mechanistic inference. Coding variant associations offer a direct route to biological insight for complex diseases and identification of validated therapeutic targets; however, appropriate mechanistic inference requires careful specification of their causal contribution to disease predisposition.


Assuntos
Diabetes Mellitus Tipo 2/genética , Alelos , Mapeamento Cromossômico/estatística & dados numéricos , Diabetes Mellitus Tipo 2/classificação , Diabetes Mellitus Tipo 2/fisiopatologia , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Predisposição Genética para Doença , Variação Genética , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Humanos , Masculino , Sequenciamento Completo do Exoma/estatística & dados numéricos
16.
Circ Arrhythm Electrophysiol ; 11(2): e005762, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29440187

RESUMO

BACKGROUND: We developed a novel electrocardiographic marker, T-wave area dispersion (TW-Ad), which measures repolarization heterogeneity by assessing interlead T-wave areas during a single cardiac cycle and tested whether it can identify patients at risk for sudden cardiac death (SCD) in the general population. METHODS AND RESULTS: TW-Ad was measured from standard digital 12-lead ECG in 5618 adults (46% men; age, 50.9±12.5 years) participating in the Health 2000 Study-an epidemiological survey representative of the Finnish adult population. Independent replication was performed in 3831 participants of the KORA S4 Study (Cooperative Health Research in the Region of Augsburg; 49% men; age, 48.7±13.7 years; mean follow-up, 8.8±1.1 years). During follow-up (7.7±1.4 years), 72 SCDs occurred in the Health 2000 Survey. Lower TW-Ad was univariately associated with SCD (0.32±0.36 versus 0.60±0.19; P<0.001); it had an area under the receiver operating characteristic curve of 0.809. TW-Ad (≤0.46) conferred a hazard ratio of 10.8 (95% confidence interval, 6.8-17.4; P<0.001) for SCD; it remained independently predictive of SCD after multivariable adjustment for clinical risk markers (hazard ratio, 4.6; 95% confidence interval, 2.7-7.4; P<0.001). Replication analyses performed in the KORA S4 Study confirmed an increased risk for cardiac death (unadjusted hazard ratio, 5.5; 95% confidence interval, 3.2-9.5; P<0.001; multivariable adjusted hazard ratio, 1.9; 95% confidence interval, 1.1-3.5; P<0.05). CONCLUSION: Low TW-Ad, reflecting increased heterogeneity of repolarization, in standard 12-lead resting ECGs is a powerful and independent predictor of SCD in the adult general population.


Assuntos
Doença das Coronárias/complicações , Morte Súbita Cardíaca/prevenção & controle , Eletrocardiografia/métodos , Inquéritos Epidemiológicos/métodos , Frequência Cardíaca/fisiologia , Medição de Risco/métodos , Adulto , Idoso , Causas de Morte/tendências , Doença das Coronárias/mortalidade , Doença das Coronárias/fisiopatologia , Estudos Transversais , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Feminino , Finlândia/epidemiologia , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Fatores de Tempo
18.
Sci Data ; 4: 170179, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29257133

RESUMO

To investigate the genetic basis of type 2 diabetes (T2D) to high resolution, the GoT2D and T2D-GENES consortia catalogued variation from whole-genome sequencing of 2,657 European individuals and exome sequencing of 12,940 individuals of multiple ancestries. Over 27M SNPs, indels, and structural variants were identified, including 99% of low-frequency (minor allele frequency [MAF] 0.1-5%) non-coding variants in the whole-genome sequenced individuals and 99.7% of low-frequency coding variants in the whole-exome sequenced individuals. Each variant was tested for association with T2D in the sequenced individuals, and, to increase power, most were tested in larger numbers of individuals (>80% of low-frequency coding variants in ~82 K Europeans via the exome chip, and ~90% of low-frequency non-coding variants in ~44 K Europeans via genotype imputation). The variants, genotypes, and association statistics from these analyses provide the largest reference to date of human genetic information relevant to T2D, for use in activities such as T2D-focused genotype imputation, functional characterization of variants or genes, and other novel analyses to detect associations between sequence variation and T2D.


Assuntos
Diabetes Mellitus Tipo 2/genética , Variação Genética , Grupo com Ancestrais do Continente Europeu , Humanos
19.
Genetics ; 207(4): 1275-1283, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29025915

RESUMO

Testing for the existence of variance components in linear mixed models is a fundamental task in many applicative fields. In statistical genetics, the score test has recently become instrumental in the task of testing an association between a set of genetic markers and a phenotype. With few markers, this amounts to set-based variance component tests, which attempt to increase power in association studies by aggregating weak individual effects. When the entire genome is considered, it allows testing for the heritability of a phenotype, defined as the proportion of phenotypic variance explained by genetics. In the popular score-based Sequence Kernel Association Test (SKAT) method, the assumed distribution of the score test statistic is uncalibrated in small samples, with a correction being computationally expensive. This may cause severe inflation or deflation of P-values, even when the null hypothesis is true. Here, we characterize the conditions under which this discrepancy holds, and show it may occur also in large real datasets, such as a dataset from the Wellcome Trust Case Control Consortium 2 (n = 13,950) study, and, in particular, when the individuals in the sample are unrelated. In these cases, the SKAT approximation tends to be highly overconservative and therefore underpowered. To address this limitation, we suggest an efficient method to calculate exact P-values for the score test in the case of a single variance component and a continuous response vector, which can speed up the analysis by orders of magnitude. Our results enable fast and accurate application of the score test in heritability and in set-based association tests. Our method is available in http://github.com/cozygene/RL-SKAT.


Assuntos
Estudos de Associação Genética/estatística & dados numéricos , Marcadores Genéticos , Variação Genética , Genoma/genética , Algoritmos , Simulação por Computador , Humanos , Modelos Genéticos , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Software
20.
BMC Bioinformatics ; 18(1): 429, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-28962546

RESUMO

BACKGROUND: Genome-wide association studies allow us to understand the genetics of complex diseases. Human metabolism provides information about the disease-causing mechanisms, so it is usual to investigate the associations between genetic variants and metabolite levels. However, only considering genetic variants and their effects on one trait ignores the possible interplay between different "omics" layers. Existing tools only consider single-nucleotide polymorphism (SNP)-SNP interactions, and no practical tool is available for large-scale investigations of the interactions between pairs of arbitrary quantitative variables. RESULTS: We developed an R package called pulver to compute p-values for the interaction term in a very large number of linear regression models. Comparisons based on simulated data showed that pulver is much faster than the existing tools. This is achieved by using the correlation coefficient to test the null-hypothesis, which avoids the costly computation of inversions. Additional tricks are a rearrangement of the order, when iterating through the different "omics" layers, and implementing this algorithm in the fast programming language C++. Furthermore, we applied our algorithm to data from the German KORA study to investigate a real-world problem involving the interplay among DNA methylation, genetic variants, and metabolite levels. CONCLUSIONS: The pulver package is a convenient and rapid tool for screening huge numbers of linear regression models for significant interaction terms in arbitrary pairs of quantitative variables. pulver is written in R and C++, and can be downloaded freely from CRAN at https://cran.r-project.org/web/packages/pulver/ .


Assuntos
Software , Algoritmos , Simulação por Computador , Ilhas de CpG/genética , Humanos , Modelos Lineares , Polimorfismo de Nucleotídeo Único/genética , Fatores de Tempo
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