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1.
Ophthalmology ; 126(1): 156-170, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29361356

RESUMO

PURPOSE: To describe the study protocol and baseline characteristics of the African Descent and Glaucoma Evaluation Study (ADAGES) III. DESIGN: Cross-sectional, case-control study. PARTICIPANTS: Three thousand two hundred sixty-six glaucoma patients and control participants without glaucoma of African or European descent were recruited from 5 study centers in different regions of the United States. METHODS: Individuals of African descent (AD) and European descent (ED) with primary open-angle glaucoma (POAG) and control participants completed a detailed demographic and medical history interview. Standardized height, weight, and blood pressure measurements were obtained. Saliva and blood samples to provide serum, plasma, DNA, and RNA were collected for standardized processing. Visual fields, stereoscopic disc photographs, and details of the ophthalmic examination were obtained and transferred to the University of California, San Diego, Data Coordinating Center for standardized processing and quality review. MAIN OUTCOME MEASURES: Participant gender, age, race, body mass index, blood pressure, history of smoking and alcohol use in POAG patients and control participants were described. Ophthalmic measures included intraocular pressure, visual field mean deviation, central corneal thickness, glaucoma medication use, or past glaucoma surgery. Ocular conditions, including diabetic retinopathy, age-related macular degeneration, and past cataract surgery, were recorded. RESULTS: The 3266 ADAGES III study participants in this report include 2146 AD POAG patients, 695 ED POAG patients, 198 AD control participants, and 227 ED control participants. The AD POAG patients and control participants were significantly younger (both, 67.4 years) than ED POAG patients and control participants (73.4 and 70.2 years, respectively). After adjusting for age, AD POAG patients had different phenotypic characteristics compared with ED POAG patients, including higher intraocular pressure, worse visual acuity and visual field mean deviation, and thinner corneas (all P < 0.001). Family history of glaucoma did not differ between AD and ED POAG patients. CONCLUSIONS: With its large sample size, extensive specimen collection, and deep phenotyping of AD and ED glaucoma patients and control participants from different regions in the United States, the ADAGES III genomics study will address gaps in our knowledge of the genetics of POAG in this high-risk population.


Assuntos
Negro ou Afro-Americano/genética , Glaucoma de Ângulo Aberto/genética , Polimorfismo de Nucleotídeo Único , Idoso , Constituição Corporal , Estudos de Casos e Controles , Estudos Transversais , Feminino , Interação Gene-Ambiente , Estudo de Associação Genômica Ampla , Genótipo , Glaucoma de Ângulo Aberto/diagnóstico , Humanos , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Projetos de Pesquisa , Acuidade Visual/fisiologia , Campos Visuais/fisiologia , População Branca/genética
2.
J Hum Genet ; 62(2): 175-184, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27535031

RESUMO

Linkage studies of complex genetic diseases have been largely replaced by genome-wide association studies, due in part to limited success in complex trait discovery. However, recent interest in rare and low-frequency variants motivates re-examination of family-based methods. In this study, we investigated the performance of two-point linkage analysis for over 1.6 million single-nucleotide polymorphisms (SNPs) combined with single variant association analysis to identify high impact variants, which are both strongly linked and associated with cardiometabolic traits in up to 1414 Hispanics from the Insulin Resistance Atherosclerosis Family Study (IRASFS). Evaluation of all 50 phenotypes yielded 83 557 000 LOD (logarithm of the odds) scores, with 9214 LOD scores ⩾3.0, 845 ⩾4.0 and 89 ⩾5.0, with a maximal LOD score of 6.49 (rs12956744 in the LAMA1 gene for tumor necrosis factor-α (TNFα) receptor 2). Twenty-seven variants were associated with P<0.005 as well as having an LOD score >4, including variants in the NFIB gene under a linkage peak with TNFα receptor 2 levels on chromosome 9. Linkage regions of interest included a broad peak (31 Mb) on chromosome 1q with acute insulin response (max LOD=5.37). This region was previously documented with type 2 diabetes in family-based studies, providing support for the validity of these results. Overall, we have demonstrated the utility of two-point linkage and association in comprehensive genome-wide array-based SNP genotypes.


Assuntos
Diabetes Mellitus Tipo 2/genética , Ligação Genética/genética , Resistência à Insulina/genética , Laminina/genética , Fatores de Transcrição NFI/genética , Fator de Necrose Tumoral alfa/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Hispânico ou Latino/genética , Humanos , Escore Lod , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Adulto Jovem
3.
Diabetes Care ; 37(4): 1157-64, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24574349

RESUMO

OBJECTIVE Given the high rates of cardiovascular disease (CVD) and associated mortality in individuals with type 2 diabetes, identifying and understanding predictors of CVD events and mortality could help inform clinical management in this high-risk group. Recent large-scale genetic studies may provide additional tools in this regard. RESEARCH DESIGN AND METHODS Genetic risk scores (GRSs) were constructed in 1,175 self-identified European American (EA) individuals comprising the family-based Diabetes Heart Study based on 1) 13 single nucleotide polymorphisms (SNPs) and 2) 30 SNPs with previously documented associations with CVD in genome-wide association studies. Associations between each GRS and a self-reported history of CVD, coronary artery calcified plaque (CAC) determined by noncontrast computed tomography scan, all-cause mortality, and CVD mortality were examined using marginal models with generalized estimating equations and Cox proportional hazards models. RESULTS The weighted 13-SNP GRS was associated with prior CVD (odds ratio [OR] 1.51 [95% CI 1.22-1.86]; P = 0.0002), CAC (ß-coefficient [ß] 0.22 [0.02-0.43]; P = 0.04) and CVD mortality (hazard ratio [HR] 1.35 [1.10-1.81]; P = 0.04) when adjusting for the other known CVD risk factors: age, sex, type 2 diabetes affection status, BMI, current smoking status, hypertension, and dyslipidemia. The weighted 30-SNP GRS was also associated with prior CVD (OR 1.33 [1.08-1.65]; P = 0.008), CAC (ß 0.29 [0.08-0.50]; P = 0.006), all-cause mortality (HR 1.28 [1.05-1.56]; P = 0.01), and CVD mortality (HR 1.46 [1.08-1.96]; P = 0.01). CONCLUSIONS These findings support the utility of two simple GRSs in examining genetic associations for adverse outcomes in EAs with type 2 diabetes.


Assuntos
Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/mortalidade , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/mortalidade , Predisposição Genética para Doença , Idoso , Doença da Artéria Coronariana/etiologia , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Placa Aterosclerótica/etiologia , Placa Aterosclerótica/genética , Polimorfismo de Nucleotídeo Único , Modelos de Riscos Proporcionais , Fatores de Risco , Tomografia Computadorizada por Raios X , População Branca
4.
J Diabetes Complications ; 28(2): 147-51, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24360973

RESUMO

AIMS: To examine the additive effect of the z-4 microsatellite polymorphism of aldose reductase gene (ALR2) and glycaemic control on risk of cataract in a prospective cohort of Chinese type 2 diabetic patients. METHODS: The (CA)n microsatellite polymorphism of ALR2 was determined using PCR followed by capillary gel electrophoresis. Cataract was defined by presence of lens opacity on direct ophthalmoscopy or history of cataract surgery. A non-linear curve approach was used to identify the threshold of glycated hemoglobin (HbA1c) at which the odds ratio (OR) for cataract started to increase. The association of z-4 allele with cataract, above and below this threshold, was assessed using multiple logistic regression analysis. RESULTS: Of the 5823 patients analyzed, 28.1% had cataracts. After adjusting for conventional risk factors and using non-z-4 carriers with HbA1c<8.0% as referent group (n = 3173), the OR (95% confidence intervals) for cataract was highest in z-4 carriers with HbA1c ≥ 8.0% [1.43 (1.05-1.96), n = 244], compared to non-z-4 carriers with HbA1c ≥ 8.0 [1.27 (1.10-1.47), n = 1836] and z-4 carriers with HbA1c<8.0%[1.01 (0.77-1.29), n = 420, P(trend) < 0.001]. This additive association remained significant after additional adjustments for drug use (P(trend) = 0.002) and renal function (P(trend) = 0.01). CONCLUSIONS: In type 2 diabetic patients with suboptimal glycaemic control, the z-4 allele of ALR2 (CA)n polymorphism was independently associated with increased susceptibility to cataracts.


Assuntos
Aldeído Redutase/genética , Glicemia/metabolismo , Catarata/sangue , Catarata/genética , Diabetes Mellitus Tipo 2/complicações , Repetições de Microssatélites , Polimorfismo Genético , Adulto , Idoso , Catarata/epidemiologia , China/epidemiologia , Estudos de Coortes , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/terapia , Retinopatia Diabética/sangue , Retinopatia Diabética/epidemiologia , Retinopatia Diabética/genética , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade
5.
Hum Mol Genet ; 22(7): 1443-56, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23297364

RESUMO

The formation of alternative DNA secondary structures can result in DNA breakage leading to cancer and other diseases. Chromosomal fragile sites, which are regions of the genome that exhibit chromosomal breakage under conditions of mild replication stress, are predicted to form stable DNA secondary structures. DNA breakage at fragile sites is associated with regions that are deleted, amplified or rearranged in cancer. Despite the correlation, unbiased examination of the ability to form secondary structures has not been evaluated in fragile sites. Here, using the Mfold program, we predict potential DNA secondary structure formation on the human chromosome 10 sequence, and utilize this analysis to compare fragile and non-fragile DNA. We found that aphidicolin (APH)-induced common fragile sites contain more sequence segments with potential high secondary structure-forming ability, and these segments clustered more densely than those in non-fragile DNA. Additionally, using a threshold of secondary structure-forming ability, we refined legitimate fragile sites within the cytogenetically defined boundaries, and identified potential fragile regions within non-fragile DNA. In vitro detection of alternative DNA structure formation and a DNA breakage cell assay were used to validate the computational predictions. Many of the regions identified by our analysis coincide with genes mutated in various diseases and regions of copy number alteration in cancer. This study supports the role of DNA secondary structures in common fragile site instability, provides a systematic method for their identification and suggests a mechanism by which DNA secondary structures can lead to human disease.


Assuntos
Sítios Frágeis do Cromossomo , Cromossomos Humanos Par 10/genética , Simulação por Computador , DNA/genética , Clivagem do DNA , Humanos , Modelos Moleculares , Neoplasias/genética , Conformação de Ácido Nucleico , Termodinâmica
6.
Nat Genet ; 44(12): 1326-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23104005

RESUMO

In Western countries, prostate cancer is the most prevalent cancer of men and one of the leading causes of cancer-related death in men. Several genome-wide association studies have yielded numerous common variants conferring risk of prostate cancer. Here, we analyzed 32.5 million variants discovered by whole-genome sequencing 1,795 Icelanders. We identified a new low-frequency variant at 8q24 associated with prostate cancer in European populations, rs188140481[A] (odds ratio (OR) = 2.90; P(combined) = 6.2 × 10(-34)), with an average risk allele frequency in controls of 0.54%. This variant is only very weakly correlated (r(2) ≤ 0.06) with previously reported risk variants at 8q24, and its association remains significant after adjustment for all known risk-associated variants. Carriers of rs188140481[A] were diagnosed with prostate cancer 1.26 years younger than non-carriers (P = 0.0059). We also report results for a previously described HOXB13 variant (rs138213197[T]), confirming it as a prostate cancer risk variant in populations from across Europe.


Assuntos
Adenocarcinoma/genética , Mutação , Neoplasias da Próstata/genética , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Linhagem Celular , Cromossomos Humanos Par 8 , Frequência do Gene , Predisposição Genética para Doença , Genoma Humano , Estudo de Associação Genômica Ampla , Proteínas de Homeodomínio/genética , Humanos , Islândia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Risco , Análise de Sequência de DNA , População Branca/genética
7.
Diabetes Care ; 35(2): 287-92, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22275441

RESUMO

OBJECTIVE: Multiple single nucleotide polymorphisms (SNPs) associated with type 2 diabetes (T2D) susceptibility have been identified in predominantly European-derived populations. These SNPs have not been extensively investigated for individual and cumulative effects on T2D risk in African Americans. RESEARCH DESIGN AND METHODS: Seventeen index T2D risk variants were genotyped in 2,652 African American case subjects with T2D and 1,393 nondiabetic control subjects. Individual SNPs and cumulative risk allele loads were assessed for association with risk for T2D. Cumulative risk was assessed by counting risk alleles and evaluating the difference in cumulative risk scores between case subjects and control subjects. A second analysis weighted risk scores (ln [OR]) based on previously reported European-derived effect sizes. RESULTS: Frequencies of risk alleles ranged from 8.6 to 99.9%. Eleven SNPs had ORs >1, and 5 from ADAMTS9, WFS1, CDKAL1, JAZF1, and TCF7L2 trended or had nominally significant evidence of T2D association (P < 0.05). Individuals carried between 13 and 29 risk alleles. Association was observed between T2D and increase in risk allele load (unweighted OR 1.04 [95% CI 1.01-1.08], P = 0.010; weighted 1.06 [1.03-1.10], P = 8.10 × 10(-5)). When TCF7L2 SNP rs7903146 was included as a covariate, the risk score was no longer associated with T2D in either model (unweighted 1.02 [0.98-1.05], P = 0.33; weighted 1.02 [0.98-1.06], P = 0.40). CONCLUSIONS: The trend of increase in risk for T2D with increasing risk allele load is similar to observations in European-derived populations; however, these analyses indicate that T2D genetic risk is primarily mediated through the effect of TCF7L2 in African Americans.


Assuntos
Diabetes Mellitus Tipo 2/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas ADAM/genética , Proteína ADAMTS9 , Adulto , Negro ou Afro-Americano/genética , Idoso , Alelos , Proteínas Correpressoras , Quinase 5 Dependente de Ciclina/genética , Proteínas de Ligação a DNA , Feminino , Predisposição Genética para Doença/genética , Genótipo , Humanos , Desequilíbrio de Ligação/genética , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , tRNA Metiltransferases
8.
Genes Chromosomes Cancer ; 50(9): 746-55, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21638519

RESUMO

To gain a better understanding of the mechanism of chromosomal translocations in cancer, we investigated the spatial proximity between CBFB and MYH11 genes involved in inv(16)(p13q22) found in patients with acute myeloid leukemia. Previous studies have demonstrated a role for spatial genome organization in the formation of tumorigenic abnormalities. The nonrandom localization of chromosomes and, more specifically, of genes appears to play a role in the mechanism of chromosomal translocations. Here, two-color fluorescence in situ hybridization and confocal microscopy were used to measure the interphase distance between CBFB and MYH11 in hematopoietic stem cells (HSCs), where inv(16)(p13q22) is believed to occur, leading to leukemia development. The measured distances in HSCs were compared with mesenchymal stem cells, peripheral blood lymphocytes, and fibroblasts, as spatial genome organization is determined to be cell-type specific. Results indicate that CBFB and MYH11 are significantly closer in HSCs compared with all other cell types examined. Furthermore, the CBFB-MYH11 distance is significantly reduced compared with CBFB and a control locus in HSCs, although separation between CBFB and the control is ∼70% of that between CBFB and MYH11 on metaphase chromosomes. HSCs were also treated with fragile site-inducing chemicals because both the genes contain translocation breakpoints within these regions. However, treatment with fragile site-inducing chemicals did not significantly affect the interphase distance. Consistent with previous studies, our results suggest that gene proximity may play a role in the formation of cancer-causing rearrangements, providing insight into the mechanism of chromosomal abnormalities in human tumors.


Assuntos
Núcleo Celular , Subunidade beta de Fator de Ligação ao Core/genética , Células-Tronco Hematopoéticas/citologia , Interfase/genética , Leucemia Mieloide Aguda/genética , Cadeias Pesadas de Miosina/genética , Translocação Genética , 2-Aminopurina/farmacologia , Afidicolina/farmacologia , Células Cultivadas , Sítios Frágeis do Cromossomo/efeitos dos fármacos , Diminazena/análogos & derivados , Diminazena/farmacologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Hibridização in Situ Fluorescente , Leucemia Mieloide Aguda/patologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Microscopia Confocal
9.
Diabetes Res Clin Pract ; 86(3): 186-92, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19782423

RESUMO

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in women. It is characterized by chronic anovulation, hyperandrogenism, obesity and a predisposition to type 2 diabetes mellitus (T2DM). Since obesity plays an important role in the etiology of PCOS, we sought to determine if variants in the perilipin gene (PLIN), a gene previously implicated in the development of obesity, were also associated with PCOS. We typed six single nucleotide polymorphisms (haplotype tagging and/or previously associated with obesity or related metabolic traits) in PLIN in 305 unrelated non-Hispanic white women (185 with PCOS and 120 without PCOS). None of the variants was associated with PCOS (P<0.05). However, the variant rs1052700*A was associated with increased risk for glucose intolerance (impaired glucose tolerance or T2DM) in both non-PCOS (OR=1.75 [1.02-3.01], P=0.044) and PCOS subjects (OR=1.67 [1.08-2.59], P=0.022). It was also associated with increased LDL (P=0.007) and total cholesterol levels (P=0.042). These results suggest that genetic variation in PLIN may affect glucose and lipid metabolism in women both with and without PCOS.


Assuntos
Glicemia/metabolismo , Variação Genética , Lipídeos/fisiologia , Fosfoproteínas/genética , Síndrome do Ovário Policístico/genética , População Branca/genética , Adulto , Índice de Massa Corporal , Proteínas de Transporte , Diabetes Mellitus Tipo 2/genética , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina/sangue , Lipídeos/sangue , Perilipina-1 , Síndrome do Ovário Policístico/sangue
10.
Nat Genet ; 41(3): 342-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19198610

RESUMO

Eosinophils are pleiotropic multifunctional leukocytes involved in initiation and propagation of inflammatory responses and thus have important roles in the pathogenesis of inflammatory diseases. Here we describe a genome-wide association scan for sequence variants affecting eosinophil counts in blood of 9,392 Icelanders. The most significant SNPs were studied further in 12,118 Europeans and 5,212 East Asians. SNPs at 2q12 (rs1420101), 2q13 (rs12619285), 3q21 (rs4857855), 5q31 (rs4143832) and 12q24 (rs3184504) reached genome-wide significance (P = 5.3 x 10(-14), 5.4 x 10(-10), 8.6 x 10(-17), 1.2 x 10(-10) and 6.5 x 10(-19), respectively). A SNP at IL1RL1 associated with asthma (P = 5.5 x 10(-12)) in a collection of ten different populations (7,996 cases and 44,890 controls). SNPs at WDR36, IL33 and MYB that showed suggestive association with eosinophil counts were also associated with atopic asthma (P = 4.2 x 10(-6), 2.2 x 10(-5) and 2.4 x 10(-4), respectively). We also found that a nonsynonymous SNP at 12q24, in SH2B3, associated significantly (P = 8.6 x 10(-8)) with myocardial infarction in six different populations (6,650 cases and 40,621 controls).


Assuntos
Asma/genética , Eosinófilos/citologia , Infarto do Miocárdio/genética , Polimorfismo de Nucleotídeo Único/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Proteínas Adaptadoras de Transporte Vesicular/genética , Algoritmos , Asma/imunologia , Asma/patologia , Estudos de Casos e Controles , Eosinófilos/patologia , Proteínas do Olho/genética , Genes myb/fisiologia , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Islândia , Proteína 1 Semelhante a Receptor de Interleucina-1 , Interleucina-33 , Interleucinas/genética , Peptídeos e Proteínas de Sinalização Intracelular , Contagem de Leucócitos , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/patologia , Proteínas/genética , Receptores de Superfície Celular/genética
11.
Diabetes ; 57(8): 2226-33, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18469204

RESUMO

OBJECTIVE: Recent genome-wide association studies have identified six novel genes for type 2 diabetes and obesity and confirmed TCF7L2 as the major type 2 diabetes gene to date in Europeans. However, the implications of these genes in Asians are unclear. RESEARCH DESIGN AND METHODS: We studied 13 associated single nucleotide polymorphisms from these genes in 3,041 patients with type 2 diabetes and 3,678 control subjects of Asian ancestry from Hong Kong and Korea. RESULTS: We confirmed the associations of TCF7L2, SLC30A8, HHEX, CDKAL1, CDKN2A/CDKN2B, IGF2BP2, and FTO with risk for type 2 diabetes, with odds ratios ranging from 1.13 to 1.35 (1.3 x 10(-12) < P(unadjusted) < 0.016). In addition, the A allele of rs8050136 at FTO was associated with increased BMI in the control subjects (P(unadjusted) = 0.008). However, we did not observe significant association of any genetic variants with surrogate measures of insulin secretion or insulin sensitivity indexes in a subset of 2,662 control subjects. Compared with subjects carrying zero, one, or two risk alleles, each additional risk allele was associated with 17% increased risk, and there was an up to 3.3-fold increased risk for type 2 diabetes in those carrying eight or more risk alleles. Despite most of the effect sizes being similar between Asians and Europeans in the meta-analyses, the ethnic differences in risk allele frequencies in most of these genes lead to variable attributable risks in these two populations. CONCLUSIONS: Our findings support the important but differential contribution of these genetic variants to type 2 diabetes and obesity in Asians compared with Europeans.


Assuntos
Povo Asiático/genética , Diabetes Mellitus Tipo 2/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Alelos , Proteínas de Transporte de Cátions/genética , Quinase 5 Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Diabetes Mellitus Tipo 2/etnologia , Feminino , Frequência do Gene , Predisposição Genética para Doença/etnologia , Predisposição Genética para Doença/genética , Genótipo , Proteínas de Homeodomínio/genética , Hong Kong/epidemiologia , Humanos , Coreia (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Obesidade/etnologia , Proteínas de Ligação a RNA/genética , Fatores de Transcrição TCF/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição , Fatores de Transcrição/genética , Transportador 8 de Zinco , tRNA Metiltransferases
12.
Nat Genet ; 39(8): 977-83, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17603485

RESUMO

We performed a genome-wide association scan to search for sequence variants conferring risk of prostate cancer using 1,501 Icelandic men with prostate cancer and 11,290 controls. Follow-up studies involving three additional case-control groups replicated an association of two variants on chromosome 17 with the disease. These two variants, 33 Mb apart, fall within a region previously implicated by family-based linkage studies on prostate cancer. The risks conferred by these variants are moderate individually (allele odds ratio of about 1.20), but because they are common, their joint population attributable risk is substantial. One of the variants is in TCF2 (HNF1beta), a gene known to be mutated in individuals with maturity-onset diabetes of the young type 5. Results from eight case-control groups, including one West African and one Chinese, demonstrate that this variant confers protection against type 2 diabetes.


Assuntos
Cromossomos Humanos Par 17 , Diabetes Mellitus Tipo 2/genética , Fator 1-beta Nuclear de Hepatócito/genética , Neoplasias da Próstata/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Haplótipos , Humanos , Masculino , Polimorfismo de Nucleotídeo Único
13.
Nephrol Dial Transplant ; 20(12): 2733-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16141456

RESUMO

BACKGROUND: The G-308A polymorphism in the promoter region of the tumor necrosis factor alpha (TNF-alpha) gene has been reported to be associated with insulin resistance and obesity, both of which may increase the risk of diabetic nephropathy. We hypothesized that this polymorphism might interact with obesity to affect development of diabetic nephropathy. METHODS: A consecutive cohort of 1281 Chinese type 2 diabetic patients was enrolled for analysis. Genotyping of TNF-alpha G-308A polymorphism was performed using a PCR-based RFLP method with NcoI digestion. The mean value of the albumin creatinine ratio (ACR) of a random spot urine sample and a timed urinary collection was used to determine albuminuric status. Diabetic nephropathy was defined as serum creatinine > or =150 micromol/L and/or mean ACR > or =25 mg/mmol. Obesity was defined as body mass index > or =25 kg/m2 using Asian criteria. RESULTS: The G-308A polymorphism was not associated with either obesity or nephropathy. Clinical characteristics were similar between GG and GA/AA genotype carriers. Amongst the obese patients, GG genotype carriers had a higher median (interquartile range) urinary ACR [3.16 (0.70, 59.10) vs 1.28 (0.48, 12.28) mg/mmol; p = 0.01] and albumin excretion rate [38.7 (12.1, 620.3) vs 21.4 (8.9, 224.0) microg/min, p = 0.03] than GA/AA carriers. On multiple logistic regression analysis, compared with non-obese GA/AA carriers, obese subjects with the GG genotype had a 2.5-fold increased risk (95% CI: 1.04-6.03; P = 0.04) of nephropathy after adjustment for confounding factors. Other independent factors for diabetic nephropathy included male sex, systolic blood pressure, triglycerides (logarithmically transformed value), and the presence of cardiovascular and microvascular complications. CONCLUSION: Our findings suggest that the GG genotype of TNF-alpha G-308A polymorphism or a genetic variant in close linkage disequilibrium may interact with obesity to increase the risk of nephropathy in Chinese Type 2 diabetic patients. Apart from the need for replication of these results, functional studies are required to clarify its significance.


Assuntos
DNA/genética , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/genética , Obesidade/complicações , Polimorfismo Genético , Fator de Necrose Tumoral alfa/genética , Idoso , Alelos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/etiologia , Feminino , Frequência do Gene , Genótipo , Hong Kong/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Obesidade/genética , Reação em Cadeia da Polimerase , Fatores de Risco
14.
J Clin Endocrinol Metab ; 90(12): 6418-23, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16189249

RESUMO

CONTEXT: Age-related declines in testosterone and IGF-I are associated with deposition of visceral fat, a component of the metabolic syndrome (MES). OBJECTIVE: Testosterone and IGF-I may interact with familial disposition to diabetes mellitus to increase the association with MES. DESIGN: We conducted a cross-sectional cohort study. SETTING: The study was conducted in a university teaching hospital. SUBJECTS: Study subjects included 179 middle-aged men with a family history of diabetes (FH) (aged 39.1 +/- 8.1 yr) and 128 men without FH (aged 43.8 +/- 8.5 yr). MAIN OUTCOME MEASURES: Clinical characteristics, frequency of MES using the World Health Organization criteria with Asian definitions of obesity (body mass index > or = 25 kg/m2), and serum levels of total testosterone, IGF-I, and high-sensitive C-reactive protein (hs-CRP) were measured. RESULTS: Men with FH had higher frequency of MES than those without FH [39.1 vs. 23.4% (P = 0.004)]. On multivariate analysis, smoking (former and current smokers), low total testosterone, and IGF-I but elevated hs-CRP levels explained 35% of the MES variance in men with FH. The frequency of MES increased with declining tertiles of total testosterone and IGF-I but increasing tertiles of hs-CRP. After adjustment for age and smoking history, subjects with all three risk factors had a 13-fold increase in risk association with MES compared with those without hormonal and inflammatory risk factors. These risk associations were not found in men without FH in whom only smoking (ex and current) and low total testosterone level were independent predictors for MES, which explained 14% of the variance. CONCLUSIONS: Clustering of FH, hormonal abnormalities, and high hs-CRP is associated with MES in Chinese middle-aged men.


Assuntos
Povo Asiático/genética , Proteína C-Reativa/metabolismo , Diabetes Mellitus Tipo 2/genética , Fator de Crescimento Insulin-Like I/metabolismo , Síndrome Metabólica/sangue , Testosterona/sangue , Adulto , Estudos de Coortes , Estudos Transversais , Humanos , Masculino , Prontuários Médicos , Síndrome Metabólica/etiologia , Pessoa de Meia-Idade , Fatores de Risco
15.
Diabetes Care ; 28(7): 1704-9, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15983323

RESUMO

OBJECTIVE: Triglyceride-rich lipoprotein particles may promote the progression of diabetic nephropathy. Patients with diabetic nephropathy have increased plasma triglycerides and reduced activity of hepatic lipase (HL), which hydrolyzes triglycerides. We hypothesized that the HL -514C-->T polymorphism, which reduces HL expression, and its interactions with polymorphisms in apolipoprotein (apo) E and apoC3 increase the risk of diabetic nephropathy. RESEARCH DESIGN AND METHODS: In a case-control study involving 374 Chinese type 2 diabetic patients with and 392 without diabetic nephropathy, we genotyped the HL -514C-->T, apoE exon 4, and apoC3 -482C-->T polymorphisms. RESULTS: HL -514T-containing genotypes (T+) were associated with diabetic nephropathy (OR = 1.7, P = 0.0009). Adjustment by multiple logistic regression for hypertension, triglycerides, sex, non-HDL cholesterol, BMI, smoking, and alcohol intake did not diminish the association (OR = 1.8, P = 0.003). The association between HL T+ genotypes and diabetic nephropathy appeared stronger in diabetic patients with apoC3 -482 non-TT genotypes (OR = 1.9, P = 0.003) or apoE epsilon2 or epsilon4 alleles (OR = 2.2, P = 0.005). Subjects with HL TT exhibited trends toward increased triglyceride and non-HDL cholesterol levels compared with CC carriers. CONCLUSIONS: HL T+ genotypes might increase the risk of developing diabetic nephropathy by slowing clearance of triglyceride-rich remnant lipoproteins. In concert with other risk factors (e.g., hyperglycemia), lipid abnormalities may damage the kidneys and endothelium, where reduced binding sites for lipases may precipitate a vicious cycle of dyslipidemia, proteinuria, and nephropathy.


Assuntos
Apolipoproteínas C/genética , Diabetes Mellitus Tipo 2/genética , Nefropatias Diabéticas/epidemiologia , Lipase/genética , Polimorfismo de Nucleotídeo Único , Apolipoproteína C-III , Estudos de Casos e Controles , Queixo , Nefropatias Diabéticas/genética , Éxons/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar , Doenças Vasculares/epidemiologia , Doenças Vasculares/genética
16.
Diabetes ; 53(10): 2676-83, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15448100

RESUMO

We conducted autosomal genome scans to map loci for metabolic syndrome (MES) and related traits in the Hong Kong Family Diabetes Study. We selected 55 families with 137 affected members (121 affected relative pairs) for nonparametric linkage analysis on MES. We also selected 179 families with 897 members (2,127 relative pairs) for variance component-based linkage analyses on seven MES-related traits: waist circumference, systolic and diastolic blood pressure (BP), triglyceride, HDL cholesterol, fasting plasma glucose, and insulin resistance index (insulin resistance index by homeostasis model assessment [HOMA%IR]). Analyses revealed three regions that showed suggestive linkage for MES and also showed overlapping signals for metabolic traits: chromosome 1 at 169.5-181.5 cM (logarithm of odds [LOD] = 4.50 for MES, 3.71 for waist circumference, and 1.24 for diastolic BP), chromosome 2 at 44.1-57.3 cM (LOD = 2.22 for MES, 2.07 for fasting plasma glucose, and 1.29 for diastolic BP), and chromosome 16 at 45.2-65.4 cM (LOD = 1.75 for MES, 1.61 for HOMA%IR, and 1.25 for HDL cholesterol). Other regions that showed suggestive linkages included chromosome 5q for diastolic BP; 2q, 3q, 6q, 9q, 10q, and 17q for triglyceride; 12p, 12q, and 22q for HDL-C; and 6q for HOMA%IR. Simulation studies demonstrated genome-wide significant linkage of the chromosome 1 region to both MES and waist circumference (P(genome-wide) = 0.002 and 0.019, respectively). In summary, we have found a susceptibility locus on chromosome 1q21-q25 involved in the pathogenesis of multiple metabolic abnormalities, in particular obesity. Our results confirm the findings of previous studies on diabetes and related phenotypes. We also suggest the locations of other loci that may contribute to the development of MES in Hong Kong Chinese.


Assuntos
Cromossomos Humanos Par 1/genética , Predisposição Genética para Doença/genética , Genoma Humano , Síndrome Metabólica/genética , Adulto , Mapeamento Cromossômico , Família , Feminino , Hong Kong , Humanos , Masculino , Locos de Características Quantitativas
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