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1.
Blood ; 133(26): 2753-2764, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31064750

RESUMO

Patients with classic hydroa vacciniforme-like lymphoproliferative disorder (HVLPD) typically have high levels of Epstein-Barr virus (EBV) DNA in T cells and/or natural killer (NK) cells in blood and skin lesions induced by sun exposure that are infiltrated with EBV-infected lymphocytes. HVLPD is very rare in the United States and Europe but more common in Asia and South America. The disease can progress to a systemic form that may result in fatal lymphoma. We report our 11-year experience with 16 HVLPD patients from the United States and England and found that whites were less likely to develop systemic EBV disease (1/10) than nonwhites (5/6). All (10/10) of the white patients were generally in good health at last follow-up, while two-thirds (4/6) of the nonwhite patients required hematopoietic stem cell transplantation. Nonwhite patients had later age of onset of HVLPD than white patients (median age, 8 vs 5 years) and higher levels of EBV DNA (median, 1 515 000 vs 250 000 copies/ml) and more often had low numbers of NK cells (83% vs 50% of patients) and T-cell clones in the blood (83% vs 30% of patients). RNA-sequencing analysis of an HVLPD skin lesion in a white patient compared with his normal skin showed increased expression of interferon-γ and chemokines that attract T cells and NK cells. Thus, white patients with HVLPD were less likely to have systemic disease with EBV and had a much better prognosis than nonwhite patients. This trial was registered at www.clinicaltrials.gov as #NCT00369421 and #NCT00032513.

2.
Circ Cardiovasc Genet ; 10(5)2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29030403

RESUMO

BACKGROUND: Genome-wide association studies have recently identified >400 loci that harbor DNA sequence variants that influence blood pressure (BP). Our earlier studies identified and validated 56 single nucleotide variants (SNVs) associated with BP from meta-analyses of exome chip genotype data. An additional 100 variants yielded suggestive evidence of association. METHODS AND RESULTS: Here, we augment the sample with 140 886 European individuals from the UK Biobank, in whom 77 of the 100 suggestive SNVs were available for association analysis with systolic BP or diastolic BP or pulse pressure. We performed 2 meta-analyses, one in individuals of European, South Asian, African, and Hispanic descent (pan-ancestry, ≈475 000), and the other in the subset of individuals of European descent (≈423 000). Twenty-one SNVs were genome-wide significant (P<5×10-8) for BP, of which 4 are new BP loci: rs9678851 (missense, SLC4A1AP), rs7437940 (AFAP1), rs13303 (missense, STAB1), and rs1055144 (7p15.2). In addition, we identified a potentially independent novel BP-associated SNV, rs3416322 (missense, SYNPO2L) at a known locus, uncorrelated with the previously reported SNVs. Two SNVs are associated with expression levels of nearby genes, and SNVs at 3 loci are associated with other traits. One SNV with a minor allele frequency <0.01, (rs3025380 at DBH) was genome-wide significant. CONCLUSIONS: We report 4 novel loci associated with BP regulation, and 1 independent variant at an established BP locus. This analysis highlights several candidate genes with variation that alter protein function or gene expression for potential follow-up.


Assuntos
Pressão Sanguínea/genética , Loci Gênicos , Antiporters/genética , Moléculas de Adesão Celular Neuronais/genética , Bases de Dados Factuais , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Proteínas dos Microfilamentos/genética , Fenótipo , Polimorfismo de Nucleotídeo Único , Receptores de Retorno de Linfócitos/genética
3.
Proc Natl Acad Sci U S A ; 114(9): 2301-2306, 2017 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-28193859

RESUMO

Genome-wide association studies (GWAS) have identified >100 independent SNPs that modulate the risk of type 2 diabetes (T2D) and related traits. However, the pathogenic mechanisms of most of these SNPs remain elusive. Here, we examined genomic, epigenomic, and transcriptomic profiles in human pancreatic islets to understand the links between genetic variation, chromatin landscape, and gene expression in the context of T2D. We first integrated genome and transcriptome variation across 112 islet samples to produce dense cis-expression quantitative trait loci (cis-eQTL) maps. Additional integration with chromatin-state maps for islets and other diverse tissue types revealed that cis-eQTLs for islet-specific genes are specifically and significantly enriched in islet stretch enhancers. High-resolution chromatin accessibility profiling using assay for transposase-accessible chromatin sequencing (ATAC-seq) in two islet samples enabled us to identify specific transcription factor (TF) footprints embedded in active regulatory elements, which are highly enriched for islet cis-eQTL. Aggregate allelic bias signatures in TF footprints enabled us de novo to reconstruct TF binding affinities genetically, which support the high-quality nature of the TF footprint predictions. Interestingly, we found that T2D GWAS loci were strikingly and specifically enriched in islet Regulatory Factor X (RFX) footprints. Remarkably, within and across independent loci, T2D risk alleles that overlap with RFX footprints uniformly disrupt the RFX motifs at high-information content positions. Together, these results suggest that common regulatory variations have shaped islet TF footprints and the transcriptome and that a confluent RFX regulatory grammar plays a significant role in the genetic component of T2D predisposition.


Assuntos
Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Genoma Humano , Ilhotas Pancreáticas/metabolismo , Locos de Características Quantitativas , Transcriptoma , Alelos , Sequência de Bases , Sítios de Ligação , Cromatina/química , Cromatina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Epigênese Genética , Perfilação da Expressão Gênica , Variação Genética , Estudo de Associação Genômica Ampla , Impressão Genômica , Humanos , Ilhotas Pancreáticas/patologia , Polimorfismo de Nucleotídeo Único , Ligação Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Fatores de Transcrição de Fator Regulador X/genética , Fatores de Transcrição de Fator Regulador X/metabolismo
4.
Nat Genet ; 48(10): 1151-1161, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27618447

RESUMO

High blood pressure is a major risk factor for cardiovascular disease and premature death. However, there is limited knowledge on specific causal genes and pathways. To better understand the genetics of blood pressure, we genotyped 242,296 rare, low-frequency and common genetic variants in up to 192,763 individuals and used ∼155,063 samples for independent replication. We identified 30 new blood pressure- or hypertension-associated genetic regions in the general population, including 3 rare missense variants in RBM47, COL21A1 and RRAS with larger effects (>1.5 mm Hg/allele) than common variants. Multiple rare nonsense and missense variant associations were found in A2ML1, and a low-frequency nonsense variant in ENPEP was identified. Our data extend the spectrum of allelic variation underlying blood pressure traits and hypertension, provide new insights into the pathophysiology of hypertension and indicate new targets for clinical intervention.


Assuntos
Pressão Sanguínea/genética , Variação Genética , Hipertensão/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos
5.
Nat Commun ; 7: 11764, 2016 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-27353450

RESUMO

Type 2 diabetes (T2D) results from the combined effects of genetic and environmental factors on multiple tissues over time. Of the >100 variants associated with T2D and related traits in genome-wide association studies (GWAS), >90% occur in non-coding regions, suggesting a strong regulatory component to T2D risk. Here to understand how T2D status, metabolic traits and genetic variation influence gene expression, we analyse skeletal muscle biopsies from 271 well-phenotyped Finnish participants with glucose tolerance ranging from normal to newly diagnosed T2D. We perform high-depth strand-specific mRNA-sequencing and dense genotyping. Computational integration of these data with epigenome data, including ATAC-seq on skeletal muscle, and transcriptome data across diverse tissues reveals that the tissue-specific genetic regulatory architecture of skeletal muscle is highly enriched in muscle stretch/super enhancers, including some that overlap T2D GWAS variants. In one such example, T2D risk alleles residing in a muscle stretch/super enhancer are linked to increased expression and alternative splicing of muscle-specific isoforms of ANK1.


Assuntos
Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Estudo de Associação Genômica Ampla , Músculo Esquelético/metabolismo , Alelos , Epigenômica , Feminino , Regulação da Expressão Gênica , Predisposição Genética para Doença , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , RNA Mensageiro , Análise de Sequência de RNA
6.
PLoS Genet ; 10(1): e1004147, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24497850

RESUMO

Genome-wide association studies (GWAS) have identified >500 common variants associated with quantitative metabolic traits, but in aggregate such variants explain at most 20-30% of the heritable component of population variation in these traits. To further investigate the impact of genotypic variation on metabolic traits, we conducted re-sequencing studies in >6,000 members of a Finnish population cohort (The Northern Finland Birth Cohort of 1966 [NFBC]) and a type 2 diabetes case-control sample (The Finland-United States Investigation of NIDDM Genetics [FUSION] study). By sequencing the coding sequence and 5' and 3' untranslated regions of 78 genes at 17 GWAS loci associated with one or more of six metabolic traits (serum levels of fasting HDL-C, LDL-C, total cholesterol, triglycerides, plasma glucose, and insulin), and conducting both single-variant and gene-level association tests, we obtained a more complete understanding of phenotype-genotype associations at eight of these loci. At all eight of these loci, the identification of new associations provides significant evidence for multiple genetic signals to one or more phenotypes, and at two loci, in the genes ABCA1 and CETP, we found significant gene-level evidence of association to non-synonymous variants with MAF<1%. Additionally, two potentially deleterious variants that demonstrated significant associations (rs138726309, a missense variant in G6PC2, and rs28933094, a missense variant in LIPC) were considerably more common in these Finnish samples than in European reference populations, supporting our prior hypothesis that deleterious variants could attain high frequencies in this isolated population, likely due to the effects of population bottlenecks. Our results highlight the value of large, well-phenotyped samples for rare-variant association analysis, and the challenge of evaluating the phenotypic impact of such variants.


Assuntos
HDL-Colesterol/genética , Colesterol/genética , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Colesterol/metabolismo , HDL-Colesterol/metabolismo , Grupo com Ancestrais do Continente Europeu , Finlândia , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Desequilíbrio de Ligação , Fenótipo , Grupos Populacionais
7.
Nat Genet ; 46(3): 234-44, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24509480

RESUMO

To further understanding of the genetic basis of type 2 diabetes (T2D) susceptibility, we aggregated published meta-analyses of genome-wide association studies (GWAS), including 26,488 cases and 83,964 controls of European, east Asian, south Asian and Mexican and Mexican American ancestry. We observed a significant excess in the directional consistency of T2D risk alleles across ancestry groups, even at SNPs demonstrating only weak evidence of association. By following up the strongest signals of association from the trans-ethnic meta-analysis in an additional 21,491 cases and 55,647 controls of European ancestry, we identified seven new T2D susceptibility loci. Furthermore, we observed considerable improvements in the fine-mapping resolution of common variant association signals at several T2D susceptibility loci. These observations highlight the benefits of trans-ethnic GWAS for the discovery and characterization of complex trait loci and emphasize an exciting opportunity to extend insight into the genetic architecture and pathogenesis of human diseases across populations of diverse ancestry.


Assuntos
Diabetes Mellitus Tipo 2/genética , Alelos , Grupo com Ancestrais do Continente Asiático/genética , Estudos de Casos e Controles , Grupo com Ancestrais do Continente Europeu/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Hispano-Americanos/genética , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco
8.
Diabetes ; 63(6): 2158-71, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24296717

RESUMO

Patients with established type 2 diabetes display both ß-cell dysfunction and insulin resistance. To define fundamental processes leading to the diabetic state, we examined the relationship between type 2 diabetes risk variants at 37 established susceptibility loci, and indices of proinsulin processing, insulin secretion, and insulin sensitivity. We included data from up to 58,614 nondiabetic subjects with basal measures and 17,327 with dynamic measures. We used additive genetic models with adjustment for sex, age, and BMI, followed by fixed-effects, inverse-variance meta-analyses. Cluster analyses grouped risk loci into five major categories based on their relationship to these continuous glycemic phenotypes. The first cluster (PPARG, KLF14, IRS1, GCKR) was characterized by primary effects on insulin sensitivity. The second cluster (MTNR1B, GCK) featured risk alleles associated with reduced insulin secretion and fasting hyperglycemia. ARAP1 constituted a third cluster characterized by defects in insulin processing. A fourth cluster (TCF7L2, SLC30A8, HHEX/IDE, CDKAL1, CDKN2A/2B) was defined by loci influencing insulin processing and secretion without a detectable change in fasting glucose levels. The final group contained 20 risk loci with no clear-cut associations to continuous glycemic traits. By assembling extensive data on continuous glycemic traits, we have exposed the diverse mechanisms whereby type 2 diabetes risk variants impact disease predisposition.


Assuntos
Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Resistência à Insulina/genética , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Locos de Características Quantitativas/genética , Alelos , Análise por Conglomerados , Feminino , Frequência do Gene , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Fatores de Transcrição/metabolismo
9.
Diabetes ; 62(11): 3943-50, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23903355

RESUMO

We used an unbiased genome-wide approach to identify exonic variants segregating with diabetes in a multigenerational Finnish family. At least eight members of this family presented with diabetes with age of diagnosis ranging from 18 to 51 years and a pattern suggesting autosomal dominant inheritance. We sequenced the exomes of four affected members of this family and performed follow-up genotyping of additional affected and unaffected family members. We uncovered a novel nonsynonymous variant (p.Trp314Arg) in the Wolfram syndrome 1 (WFS1) gene that segregates completely with the diabetic phenotype. Multipoint parametric linkage analysis with 13 members of this family identified a single linkage signal with maximum logarithm of odds score 3.01 at 4p16.2-p16.1, corresponding to a region harboring the WFS1 locus. Functional studies demonstrate a role for this variant in endoplasmic reticulum stress, which is consistent with the ß-cell failure phenotype seen in mutation carriers. This represents the first compelling report of a mutation in WFS1 associated with dominantly inherited nonsyndromic adult-onset diabetes.


Assuntos
Diabetes Mellitus/genética , Proteínas de Membrana/genética , Síndrome de Wolfram/genética , Adolescente , Adulto , Estresse do Retículo Endoplasmático , Exoma/genética , Feminino , Genes Dominantes , Ligação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem
10.
PLoS Genet ; 9(3): e1003379, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23555291

RESUMO

Genome-wide association studies (GWAS) have identified ~100 loci associated with blood lipid levels, but much of the trait heritability remains unexplained, and at most loci the identities of the trait-influencing variants remain unknown. We conducted a trans-ethnic fine-mapping study at 18, 22, and 18 GWAS loci on the Metabochip for their association with triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), respectively, in individuals of African American (n = 6,832), East Asian (n = 9,449), and European (n = 10,829) ancestry. We aimed to identify the variants with strongest association at each locus, identify additional and population-specific signals, refine association signals, and assess the relative significance of previously described functional variants. Among the 58 loci, 33 exhibited evidence of association at P<1 × 10(-4) in at least one ancestry group. Sequential conditional analyses revealed that ten, nine, and four loci in African Americans, Europeans, and East Asians, respectively, exhibited two or more signals. At these loci, accounting for all signals led to a 1.3- to 1.8-fold increase in the explained phenotypic variance compared to the strongest signals. Distinct signals across ancestry groups were identified at PCSK9 and APOA5. Trans-ethnic analyses narrowed the signals to smaller sets of variants at GCKR, PPP1R3B, ABO, LCAT, and ABCA1. Of 27 variants reported previously to have functional effects, 74% exhibited the strongest association at the respective signal. In conclusion, trans-ethnic high-density genotyping and analysis confirm the presence of allelic heterogeneity, allow the identification of population-specific variants, and limit the number of candidate SNPs for functional studies.


Assuntos
Apolipoproteínas A/genética , Estudo de Associação Genômica Ampla , Pró-Proteína Convertases/genética , Serina Endopeptidases/genética , Afro-Americanos/genética , Apolipoproteína A-V , HDL-Colesterol/sangue , HDL-Colesterol/genética , LDL-Colesterol/sangue , LDL-Colesterol/genética , Grupo com Ancestrais do Continente Europeu/genética , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas HDL/genética , Lipoproteínas LDL/sangue , Lipoproteínas LDL/genética , Pró-Proteína Convertase 9 , Triglicerídeos/sangue , Triglicerídeos/genética
11.
Diabetes ; 62(10): 3618-26, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23557707

RESUMO

We investigated the association of the levels of ketone bodies (KBs) with hyperglycemia and with 62 genetic risk variants regulating glucose levels or type 2 diabetes in the population-based Metabolic Syndrome in Men (METSIM) study, including 9,398 Finnish men without diabetes or newly diagnosed type 2 diabetes. Increasing fasting and 2-h plasma glucose levels were associated with elevated levels of acetoacetate (AcAc) and ß-hydroxybutyrate (BHB). AcAc and BHB predicted an increase in the glucose area under the curve in an oral glucose tolerance test, and AcAc predicted the conversion to type 2 diabetes in a 5-year follow-up of the METSIM cohort. Impaired insulin secretion, but not insulin resistance, explained these findings. Of the 62 single nucleotide polymorphisms associated with the risk of type 2 diabetes or hyperglycemia, the glucose-increasing C allele of GCKR significantly associated with elevated levels of fasting BHB levels. Adipose tissue mRNA expression levels of genes involved in ketolysis were significantly associated with insulin sensitivity (Matsuda index). In conclusion, high levels of KBs predicted subsequent worsening of hyperglycemia, and a common variant of GCKR was significantly associated with BHB levels.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Hiperglicemia/sangue , Corpos Cetônicos/sangue , Polimorfismo de Nucleotídeo Único , Ácido 3-Hidroxibutírico/sangue , Acetoacetatos/sangue , Área Sob a Curva , Biomarcadores/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Grupo com Ancestrais do Continente Europeu/genética , Jejum , Finlândia/epidemiologia , Estudo de Associação Genômica Ampla , Teste de Tolerância a Glucose , Humanos , Hiperglicemia/epidemiologia , Hiperglicemia/genética , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco
12.
Nucleic Acids Res ; 41(6): e70, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23314155

RESUMO

Transgenic animals are extensively used to model human disease. Typically, the transgene copy number is estimated, but the exact integration site and configuration of the foreign DNA remains uncharacterized. When transgenes have been closely examined, some unexpected configurations have been found. Here, we describe a method to recover transgene insertion sites and assess structural rearrangements of host and transgene DNA using microarray hybridization and targeted sequence capture. We used information about the transgene insertion site to develop a polymerase chain reaction genotyping assay to distinguish heterozygous from homozygous transgenic animals. Although we worked with a bacterial artificial chromosome transgenic mouse line, this method can be used to analyse the integration site and configuration of any foreign DNA in a sequenced genome.


Assuntos
Técnicas de Genotipagem , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Análise de Sequência de DNA , Transgenes , Animais , Cromossomos Artificiais Bacterianos , Camundongos , Camundongos Transgênicos , Reação em Cadeia da Polimerase
13.
Diabetes ; 61(7): 1895-902, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22553379

RESUMO

We investigated the association of glycemia and 43 genetic risk variants for hyperglycemia/type 2 diabetes with amino acid levels in the population-based Metabolic Syndrome in Men (METSIM) Study, including 9,369 nondiabetic or newly diagnosed type 2 diabetic Finnish men. Plasma levels of eight amino acids were measured with proton nuclear magnetic resonance spectroscopy. Increasing fasting and 2-h plasma glucose levels were associated with increasing levels of several amino acids and decreasing levels of histidine and glutamine. Alanine, leucine, isoleucine, tyrosine, and glutamine predicted incident type 2 diabetes in a 4.7-year follow-up of the METSIM Study, and their effects were largely mediated by insulin resistance (except for glutamine). We also found significant correlations between insulin sensitivity (Matsuda insulin sensitivity index) and mRNA expression of genes regulating amino acid degradation in 200 subcutaneous adipose tissue samples. Only 1 of 43 risk single nucleotide polymorphisms for type 2 diabetes or hyperglycemia, the glucose-increasing major C allele of rs780094 of GCKR, was significantly associated with decreased levels of alanine and isoleucine and elevated levels of glutamine. In conclusion, the levels of branched-chain, aromatic amino acids and alanine increased and the levels of glutamine and histidine decreased with increasing glycemia, reflecting, at least in part, insulin resistance. Only one single nucleotide polymorphism regulating hyperglycemia was significantly associated with amino acid levels.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Aminoácidos/sangue , Hiperglicemia/genética , Tecido Adiposo/metabolismo , Idoso , Glicemia/análise , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/genética , Finlândia , Regulação da Expressão Gênica/genética , Predisposição Genética para Doença , Humanos , Resistência à Insulina/genética , Masculino , Pessoa de Meia-Idade
14.
Circ Cardiovasc Genet ; 5(2): 242-9, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22399527

RESUMO

BACKGROUND: Genome-wide association (GWA) studies have identified several susceptibility loci for metabolic syndrome (MetS) component traits, but have had variable success in identifying susceptibility loci to the syndrome as an entity. We conducted a GWA study on MetS and its component traits in 4 Finnish cohorts consisting of 2637 MetS cases and 7927 controls, both free of diabetes, and followed the top loci in an independent sample with transcriptome and nuclear magnetic resonance-based metabonomics data. Furthermore, we tested for loci associated with multiple MetS component traits using factor analysis, and built a genetic risk score for MetS. METHODS AND RESULTS: A previously known lipid locus, APOA1/C3/A4/A5 gene cluster region (SNP rs964184), was associated with MetS in all 4 study samples (P=7.23×10(-9) in meta-analysis). The association was further supported by serum metabolite analysis, where rs964184 was associated with various very low density lipoprotein, triglyceride, and high-density lipoprotein metabolites (P=0.024-1.88×10(-5)). Twenty-two previously identified susceptibility loci for individual MetS component traits were replicated in our GWA and factor analysis. Most of these were associated with lipid phenotypes, and none with 2 or more uncorrelated MetS components. A genetic risk score, calculated as the number of risk alleles in loci associated with individual MetS traits, was strongly associated with MetS status. CONCLUSIONS: Our findings suggest that genes from lipid metabolism pathways have the key role in the genetic background of MetS. We found little evidence for pleiotropy linking dyslipidemia and obesity to the other MetS component traits, such as hypertension and glucose intolerance.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Metabolismo dos Lipídeos , Síndrome Metabólica/genética , Adulto , Feminino , Humanos , Masculino , Síndrome Metabólica/metabolismo , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Risco
15.
Diabetes ; 61(5): 1291-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22415877

RESUMO

Gene-lifestyle interactions have been suggested to contribute to the development of type 2 diabetes. Glucose levels 2 h after a standard 75-g glucose challenge are used to diagnose diabetes and are associated with both genetic and lifestyle factors. However, whether these factors interact to determine 2-h glucose levels is unknown. We meta-analyzed single nucleotide polymorphism (SNP) × BMI and SNP × physical activity (PA) interaction regression models for five SNPs previously associated with 2-h glucose levels from up to 22 studies comprising 54,884 individuals without diabetes. PA levels were dichotomized, with individuals below the first quintile classified as inactive (20%) and the remainder as active (80%). BMI was considered a continuous trait. Inactive individuals had higher 2-h glucose levels than active individuals (ß = 0.22 mmol/L [95% CI 0.13-0.31], P = 1.63 × 10(-6)). All SNPs were associated with 2-h glucose (ß = 0.06-0.12 mmol/allele, P ≤ 1.53 × 10(-7)), but no significant interactions were found with PA (P > 0.18) or BMI (P ≥ 0.04). In this large study of gene-lifestyle interaction, we observed no interactions between genetic and lifestyle factors, both of which were associated with 2-h glucose. It is perhaps unlikely that top loci from genome-wide association studies will exhibit strong subgroup-specific effects, and may not, therefore, make the best candidates for the study of interactions.


Assuntos
Glicemia/genética , Glicemia/metabolismo , Regulação da Expressão Gênica/fisiologia , Atividade Motora/fisiologia , Índice de Massa Corporal , Epigênese Genética , Genótipo , Humanos , Estilo de Vida , Polimorfismo de Nucleotídeo Único
16.
Diabetes ; 60(5): 1608-16, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21421807

RESUMO

OBJECTIVE: We investigated the effects of 34 genetic risk variants for hyperglycemia/type 2 diabetes on lipoprotein subclasses and particle composition in a large population-based cohort. RESEARCH DESIGN AND METHODS: The study included 6,580 nondiabetic Finnish men from the population-based Metabolic Syndrome in Men (METSIM) study (aged 57 ± 7 years; BMI 26.8 ± 3.7 kg/m(2)). Genotyping of 34 single nucleotide polymorphism (SNPs) for hyperglycemia/type 2 diabetes was performed. Proton nuclear magnetic resonance spectroscopy was used to measure particle concentrations of 14 lipoprotein subclasses and their composition in native serum samples. RESULTS: The glucose-increasing allele of rs780094 in GCKR was significantly associated with low concentrations of VLDL particles (independently of their size) and small LDL and was nominally associated with low concentrations of intermediate-density lipoprotein, all LDL subclasses, and high concentrations of very large and large HDL particles. The glucose-increasing allele of rs174550 in FADS1 was significantly associated with high concentrations of very large and large HDL particles and nominally associated with low concentrations of all VLDL particles. SNPs rs10923931 in NOTCH2 and rs757210 in HNF1B genes showed nominal or significant associations with several lipoprotein traits. The genetic risk score of 34 SNPs was not associated with any of the lipoprotein subclasses. CONCLUSIONS: Four of the 34 risk loci for type 2 diabetes or hyperglycemia (GCKR, FADS1, NOTCH2, and HNF1B) were significantly associated with lipoprotein traits. A GCKR variant predominantly affected the concentration of VLDL, and the FADS1 variant affected very large and large HDL particles. Only a limited number of risk loci for hyperglycemia/type 2 diabetes significantly affect lipoprotein metabolism.


Assuntos
Diabetes Mellitus Tipo 2/genética , Hiperglicemia/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , VLDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Grupo com Ancestrais do Continente Europeu , Ácidos Graxos Dessaturases/sangue , Genótipo , Humanos , Hiperglicemia/sangue , Lipoproteínas HDL/sangue , Lipoproteínas IDL/sangue , Lipoproteínas LDL/sangue , Lipoproteínas VLDL/sangue , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Receptor Notch2/sangue
17.
Genome Res ; 20(10): 1420-31, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20810667

RESUMO

Massively parallel DNA sequencing technologies have greatly increased our ability to generate large amounts of sequencing data at a rapid pace. Several methods have been developed to enrich for genomic regions of interest for targeted sequencing. We have compared three of these methods: Molecular Inversion Probes (MIP), Solution Hybrid Selection (SHS), and Microarray-based Genomic Selection (MGS). Using HapMap DNA samples, we compared each of these methods with respect to their ability to capture an identical set of exons and evolutionarily conserved regions associated with 528 genes (2.61 Mb). For sequence analysis, we developed and used a novel Bayesian genotype-assigning algorithm, Most Probable Genotype (MPG). All three capture methods were effective, but sensitivities (percentage of targeted bases associated with high-quality genotypes) varied for an equivalent amount of pass-filtered sequence: for example, 70% (MIP), 84% (SHS), and 91% (MGS) for 400 Mb. In contrast, all methods yielded similar accuracies of >99.84% when compared to Infinium 1M SNP BeadChip-derived genotypes and >99.998% when compared to 30-fold coverage whole-genome shotgun sequencing data. We also observed a low false-positive rate with all three methods; of the heterozygous positions identified by each of the capture methods, >99.57% agreed with 1M SNP BeadChip, and >98.840% agreed with the whole-genome shotgun data. In addition, we successfully piloted the genomic enrichment of a set of 12 pooled samples via the MGS method using molecular bar codes. We find that these three genomic enrichment methods are highly accurate and practical, with sensitivities comparable to that of 30-fold coverage whole-genome shotgun data.


Assuntos
Diabetes Mellitus Tipo 2/genética , Genoma Humano , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Análise de Sequência de DNA/métodos , Algoritmos , Teorema de Bayes , DNA/genética , Sondas de DNA/genética , Éxons , Genótipo , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Diabetes ; 59(12): 3229-39, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20858683

RESUMO

OBJECTIVE: Glycated hemoglobin (HbA1(c)), used to monitor and diagnose diabetes, is influenced by average glycemia over a 2- to 3-month period. Genetic factors affecting expression, turnover, and abnormal glycation of hemoglobin could also be associated with increased levels of HbA1(c). We aimed to identify such genetic factors and investigate the extent to which they influence diabetes classification based on HbA1(c) levels. RESEARCH DESIGN AND METHODS: We studied associations with HbA1(c) in up to 46,368 nondiabetic adults of European descent from 23 genome-wide association studies (GWAS) and 8 cohorts with de novo genotyped single nucleotide polymorphisms (SNPs). We combined studies using inverse-variance meta-analysis and tested mediation by glycemia using conditional analyses. We estimated the global effect of HbA1(c) loci using a multilocus risk score, and used net reclassification to estimate genetic effects on diabetes screening. RESULTS: Ten loci reached genome-wide significant association with HbA(1c), including six new loci near FN3K (lead SNP/P value, rs1046896/P = 1.6 × 10⁻²6), HFE (rs1800562/P = 2.6 × 10⁻²°), TMPRSS6 (rs855791/P = 2.7 × 10⁻¹4), ANK1 (rs4737009/P = 6.1 × 10⁻¹²), SPTA1 (rs2779116/P = 2.8 × 10⁻9) and ATP11A/TUBGCP3 (rs7998202/P = 5.2 × 10⁻9), and four known HbA1(c) loci: HK1 (rs16926246/P = 3.1 × 10⁻54), MTNR1B (rs1387153/P = 4.0 × 10⁻¹¹), GCK (rs1799884/P = 1.5 × 10⁻²°) and G6PC2/ABCB11 (rs552976/P = 8.2 × 10⁻¹8). We show that associations with HbA1(c) are partly a function of hyperglycemia associated with 3 of the 10 loci (GCK, G6PC2 and MTNR1B). The seven nonglycemic loci accounted for a 0.19 (% HbA1(c)) difference between the extreme 10% tails of the risk score, and would reclassify ∼2% of a general white population screened for diabetes with HbA1(c). CONCLUSIONS: GWAS identified 10 genetic loci reproducibly associated with HbA1(c). Six are novel and seven map to loci where rarer variants cause hereditary anemias and iron storage disorders. Common variants at these loci likely influence HbA1(c) levels via erythrocyte biology, and confer a small but detectable reclassification of diabetes diagnosis by HbA1(c).


Assuntos
Variação Genética , Hemoglobina A Glicada/genética , Adulto , Glicemia/metabolismo , Índice de Massa Corporal , Mapeamento Cromossômico , Estudos de Coortes , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Metanálise como Assunto , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
19.
Nat Genet ; 42(7): 579-89, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20581827

RESUMO

By combining genome-wide association data from 8,130 individuals with type 2 diabetes (T2D) and 38,987 controls of European descent and following up previously unidentified meta-analysis signals in a further 34,412 cases and 59,925 controls, we identified 12 new T2D association signals with combined P<5x10(-8). These include a second independent signal at the KCNQ1 locus; the first report, to our knowledge, of an X-chromosomal association (near DUSP9); and a further instance of overlap between loci implicated in monogenic and multifactorial forms of diabetes (at HNF1A). The identified loci affect both beta-cell function and insulin action, and, overall, T2D association signals show evidence of enrichment for genes involved in cell cycle regulation. We also show that a high proportion of T2D susceptibility loci harbor independent association signals influencing apparently unrelated complex traits.


Assuntos
Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença/genética , Genoma Humano/genética , Polimorfismo de Nucleotídeo Único , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Fosfatases de Especificidade Dupla/genética , Jejum/sangue , Dosagem de Genes , Perfilação da Expressão Gênica , Heterogeneidade Genética , Estudo de Associação Genômica Ampla , Fator 1-alfa Nuclear de Hepatócito/genética , Humanos , Canal de Potássio KCNQ1/genética , Metanálise como Assunto , Fosfatases da Proteína Quinase Ativada por Mitógeno/genética
20.
Diabetes ; 59(5): 1266-75, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20185807

RESUMO

OBJECTIVE Recent genome-wide association studies have revealed loci associated with glucose and insulin-related traits. We aimed to characterize 19 such loci using detailed measures of insulin processing, secretion, and sensitivity to help elucidate their role in regulation of glucose control, insulin secretion and/or action. RESEARCH DESIGN AND METHODS We investigated associations of loci identified by the Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC) with circulating proinsulin, measures of insulin secretion and sensitivity from oral glucose tolerance tests (OGTTs), euglycemic clamps, insulin suppression tests, or frequently sampled intravenous glucose tolerance tests in nondiabetic humans (n = 29,084). RESULTS The glucose-raising allele in MADD was associated with abnormal insulin processing (a dramatic effect on higher proinsulin levels, but no association with insulinogenic index) at extremely persuasive levels of statistical significance (P = 2.1 x 10(-71)). Defects in insulin processing and insulin secretion were seen in glucose-raising allele carriers at TCF7L2, SCL30A8, GIPR, and C2CD4B. Abnormalities in early insulin secretion were suggested in glucose-raising allele carriers at MTNR1B, GCK, FADS1, DGKB, and PROX1 (lower insulinogenic index; no association with proinsulin or insulin sensitivity). Two loci previously associated with fasting insulin (GCKR and IGF1) were associated with OGTT-derived insulin sensitivity indices in a consistent direction. CONCLUSIONS Genetic loci identified through their effect on hyperglycemia and/or hyperinsulinemia demonstrate considerable heterogeneity in associations with measures of insulin processing, secretion, and sensitivity. Our findings emphasize the importance of detailed physiological characterization of such loci for improved understanding of pathways associated with alterations in glucose homeostasis and eventually type 2 diabetes.


Assuntos
Loci Gênicos/fisiologia , Glucose/genética , Insulina/genética , Alelos , Ácidos Graxos Dessaturases/genética , Loci Gênicos/genética , Estudo de Associação Genômica Ampla , Glucose/metabolismo , Proteínas de Homeodomínio/genética , Humanos , Insulina/metabolismo , Metanálise como Assunto , Polimorfismo de Nucleotídeo Único/genética , Proteínas Serina-Treonina Quinases/genética , Receptores dos Hormônios Gastrointestinais/genética , Fatores de Transcrição TCF/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição , Proteínas Supressoras de Tumor/genética
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