Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 41
Filtrar
1.
Hum Mol Genet ; 30(22): 2190-2204, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34165540

RESUMO

Central obesity is a leading health concern with a great burden carried by ethnic minority populations, especially Hispanics/Latinos. Genetic factors contribute to the obesity burden overall and to inter-population differences. We aimed to identify the loci associated with central adiposity measured as waist-to-hip ratio (WHR), waist circumference (WC) and hip circumference (HIP) adjusted for body mass index (adjBMI) by using the Hispanic Community Health Study/Study of Latinos (HCHS/SOL); determine if differences in associations differ by background group within HCHS/SOL and determine whether previously reported associations generalize to HCHS/SOL. Our analyses included 7472 women and 5200 men of mainland (Mexican, Central and South American) and Caribbean (Puerto Rican, Cuban and Dominican) background residing in the USA. We performed genome-wide association analyses stratified and combined across sexes using linear mixed-model regression. We identified 16 variants for waist-to-hip ratio adjusted for body mass index (WHRadjBMI), 22 for waist circumference adjusted for body mass index (WCadjBMI) and 28 for hip circumference adjusted for body mass index (HIPadjBMI), which reached suggestive significance (P < 1 × 10-6). Many loci exhibited differences in strength of associations by ethnic background and sex. We brought a total of 66 variants forward for validation in cohorts (N = 34 161) with participants of Hispanic/Latino, African and European descent. We confirmed four novel loci (P < 0.05 and consistent direction of effect, and P < 5 × 10-8 after meta-analysis), including two for WHRadjBMI (rs13301996, rs79478137); one for WCadjBMI (rs3168072) and one for HIPadjBMI (rs28692724). Also, we generalized previously reported associations to HCHS/SOL, (8 for WHRadjBMI, 10 for WCadjBMI and 12 for HIPadjBMI). Our study highlights the importance of large-scale genomic studies in ancestrally diverse Hispanic/Latino populations for identifying and characterizing central obesity susceptibility that may be ancestry-specific.

2.
J Clin Endocrinol Metab ; 105(4)2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31714576

RESUMO

CONTEXT: Genome-wide association studies have identified more than 450 single nucleotide polymorphisms (SNPs) for type 2 diabetes (T2D). OBJECTIVE: To facilitate use of these SNPs in future genetic risk score (GRS)-based analyses, we aimed to classify the SNPs based on physiology. We also sought to validate GRS associations with insulin-related traits in deeply phenotyped Mexican Americans. DESIGN, SETTING, AND PARTICIPANTS: A total of 457 T2D SNPs from the literature were assigned physiologic function based on association studies and cluster analyses. All SNPs (All-GRS), beta-cell (BC-GRS), insulin resistance (IR-GRS), lipodystrophy (Lipo-GRS), and body mass index plus lipids (B + L-GRS) were evaluated for association with diabetes and indices of insulin secretion (from oral glucose tolerance test), insulin sensitivity and insulin clearance (from euglycemic clamp), and adiposity and lipid markers in 1587 Mexican Americans. RESULTS: Of the 457 SNPs, 52 were classified as BC, 30 as IR, 12 as Lipo, 12 as B + L, whereas physiologic function of 351 was undefined. All-GRS was strongly associated with T2D. Among nondiabetic Mexican Americans, BC-GRS was associated with reduced insulinogenic index, IR-GRS was associated with reduced insulin sensitivity, and Lipo-GRS was associated with reduced adiposity. B + L-GRS was associated with increased insulin clearance. The latter did not replicate in an independent cohort wherein insulin clearance was assessed by a different method. CONCLUSIONS: Supporting their utility, BC-GRS, IR-GRS, and Lipo-GRS, based on SNPs discovered largely in Europeans, exhibited expected associations in Mexican Americans. The novel association of B + L-GRS with insulin clearance suggests that impaired ability to reduce insulin clearance in compensation for IR may play a role in the pathogenesis of T2D. Whether this applies to other ethnic groups remains to be determined.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Secreção de Insulina/genética , Insulina/metabolismo , Polimorfismo de Nucleotídeo Único , Adulto , Biomarcadores/análise , Índice de Massa Corporal , Grupos Étnicos/genética , Feminino , Seguimentos , Genótipo , Humanos , Resistência à Insulina/genética , Masculino , Pessoa de Meia-Idade , Fenótipo , Prognóstico , Fatores de Risco , Estados Unidos/epidemiologia
3.
Obesity (Silver Spring) ; 27(8): 1331-1337, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31219225

RESUMO

OBJECTIVE: Populations of Mexican American ancestry are at an increased risk for nonalcoholic fatty liver disease. The objective of this study was to determine whether loci in known and novel genes were associated with variation in aspartate aminotransferase (AST) (n = 3,644), alanine aminotransferase (ALT) (n = 3,595), and gamma-glutamyl transferase (GGT) (n = 1,577) levels by conducting the first genome-wide association study (GWAS) of liver enzymes, which commonly measure liver function, in individuals of Mexican American ancestry. METHODS: Levels of AST, ALT, and GGT were determined by enzymatic colorimetric assays. A multi-cohort GWAS of individuals of Mexican American ancestry was performed. Single-nucleotide polymorphisms (SNP) were tested for association with liver outcomes by multivariable linear regression using an additive genetic model. Association analyses were conducted separately in each cohort, followed by a nonparametric meta-analysis. RESULTS: In the PNPLA3 gene, rs4823173 (P = 3.44 × 10-10 ), rs2896019 (P = 7.29 × 10-9 ), and rs2281135 (P = 8.73 × 10-9 ) were significantly associated with AST levels. Although not genome-wide significant, these same SNPs were the top hits for ALT (P = 7.12 × 10-8 , P = 1.98 × 10-7 , and P = 1.81 × 10-7 , respectively). The strong correlation (r2 = 1.0) for these SNPs indicated a single hit in the PNPLA3 gene. No genome-wide significant associations were found for GGT. CONCLUSIONS: PNPLA3, a locus previously identified with ALT, AST, and nonalcoholic fatty liver disease in European and Japanese GWAS, is also associated with liver enzymes in populations of Mexican American ancestry.


Assuntos
Alanina Transaminase/genética , Aspartato Aminotransferases/genética , Lipase/genética , Proteínas de Membrana/genética , Americanos Mexicanos/genética , Hepatopatia Gordurosa não Alcoólica/genética , Adulto , Feminino , Loci Gênicos , Estudo de Associação Genômica Ampla , Humanos , Modelos Lineares , Fígado/enzimologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/etnologia , Polimorfismo de Nucleotídeo Único , gama-Glutamiltransferase/genética
4.
Obesity (Silver Spring) ; 27(3): 434-443, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30801985

RESUMO

OBJECTIVE: Aging is associated with impaired insulin sensitivity and increased prevalence of type 2 diabetes. However, it remains unclear whether aging-associated insulin resistance is due to increased adiposity or other age-related factors. To address this question, the impact of aging on insulin sensitivity was investigated independently of changes in body composition. METHODS: Cohorts of mice aged 4 to 8 months ("young") and 18 to 27 months ("aged") exhibiting similar body composition were characterized for glucose metabolism on chow and high-fat diets. Insulin sensitivity was assessed by hyperinsulinemic-euglycemic clamp analyses. The relationship between aging and insulin resistance in humans was investigated in 1,250 nondiabetic Mexican Americans who underwent hyperinsulinemic-euglycemic clamps. RESULTS: In mice with similar body composition, age had no detrimental effect on plasma glucose and insulin levels. While aging did not diminish glucose tolerance, hyperinsulinemic-euglycemic clamps demonstrated impaired insulin sensitivity and reduced insulin clearance in aged mice on chow and high-fat diets. Consistent with results in the mouse, age remained an independent determinant of insulin resistance after adjustment for body composition in Mexican American males. CONCLUSIONS: This study demonstrates that in addition to altered body composition, adiposity-independent mechanisms also contribute to aging-associated insulin resistance in mice and humans.


Assuntos
Adiposidade/fisiologia , Resistência à Insulina/genética , Adulto , Animais , Feminino , Humanos , Masculino , Camundongos , Fenótipo
5.
Nat Commun ; 10(1): 29, 2019 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-30604766

RESUMO

Chronic kidney disease (CKD) affects ~10% of the global population, with considerable ethnic differences in prevalence and aetiology. We assemble genome-wide association studies of estimated glomerular filtration rate (eGFR), a measure of kidney function that defines CKD, in 312,468 individuals of diverse ancestry. We identify 127 distinct association signals with homogeneous effects on eGFR across ancestries and enrichment in genomic annotations including kidney-specific histone modifications. Fine-mapping reveals 40 high-confidence variants driving eGFR associations and highlights putative causal genes with cell-type specific expression in glomerulus, and in proximal and distal nephron. Mendelian randomisation supports causal effects of eGFR on overall and cause-specific CKD, kidney stone formation, diastolic blood pressure and hypertension. These results define novel molecular mechanisms and putative causal genes for eGFR, offering insight into clinical outcomes and routes to CKD treatment development.


Assuntos
Taxa de Filtração Glomerular/genética , Hipertensão/genética , Cálculos Renais/genética , Rim/fisiopatologia , Insuficiência Renal Crônica/genética , Adulto , Idoso , Pressão Sanguínea/genética , Grupos Étnicos/genética , Feminino , Loci Gênicos/genética , Estudo de Associação Genômica Ampla , Código das Histonas/genética , Histonas/metabolismo , Humanos , Hipertensão/etnologia , Hipertensão/fisiopatologia , Cálculos Renais/etnologia , Cálculos Renais/fisiopatologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Insuficiência Renal Crônica/etnologia , Insuficiência Renal Crônica/fisiopatologia
6.
PLoS One ; 13(7): e0200486, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30044860

RESUMO

Current knowledge of the genetic architecture of key reproductive events across the female life course is largely based on association studies of European descent women. The relevance of known loci for age at menarche (AAM) and age at natural menopause (ANM) in diverse populations remains unclear. We investigated 32 AAM and 14 ANM previously-identified loci and sought to identify novel loci in a trans-ethnic array-wide study of 196,483 SNPs on the MetaboChip (Illumina, Inc.). A total of 45,364 women of diverse ancestries (African, Hispanic/Latina, Asian American and American Indian/Alaskan Native) in the Population Architecture using Genomics and Epidemiology (PAGE) Study were included in cross-sectional analyses of AAM and ANM. Within each study we conducted a linear regression of SNP associations with self-reported or medical record-derived AAM or ANM (in years), adjusting for birth year, population stratification, and center/region, as appropriate, and meta-analyzed results across studies using multiple meta-analytic techniques. For both AAM and ANM, we observed more directionally consistent associations with the previously reported risk alleles than expected by chance (p-valuesbinomial≤0.01). Eight densely genotyped reproductive loci generalized significantly to at least one non-European population. We identified one trans-ethnic array-wide SNP association with AAM and two significant associations with ANM, which have not been described previously. Additionally, we observed evidence of independent secondary signals at three of six AAM trans-ethnic loci. Our findings support the transferability of reproductive trait loci discovered in European women to women of other race/ethnicities and indicate the presence of additional trans-ethnic associations both at both novel and established loci. These findings suggest the benefit of including diverse populations in future studies of the genetic architecture of female growth and development.


Assuntos
Variação Biológica da População/genética , Menarca/genética , Menopausa/genética , Fatores Etários , Alelos , Variação Biológica da População/etnologia , Feminino , Loci Gênicos/genética , Genótipo , Humanos , Menarca/etnologia , Menopausa/etnologia , Fenótipo , Polimorfismo de Nucleotídeo Único
7.
J Clin Endocrinol Metab ; 103(3): 991-1004, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29325096

RESUMO

Context: Serum estradiol (E2) and estrone (E1) levels exhibit substantial heritability. Objective: To investigate the genetic regulation of serum E2 and E1 in men. Design, Setting, and Participants: Genome-wide association study in 11,097 men of European origin from nine epidemiological cohorts. Main Outcome Measures: Genetic determinants of serum E2 and E1 levels. Results: Variants in/near CYP19A1 demonstrated the strongest evidence for association with E2, resolving to three independent signals. Two additional independent signals were found on the X chromosome; FAMily with sequence similarity 9, member B (FAM9B), rs5934505 (P = 3.4 × 10-8) and Xq27.3, rs5951794 (P = 3.1 × 10-10). E1 signals were found in CYP19A1 (rs2899472, P = 5.5 × 10-23), in Tripartite motif containing 4 (TRIM4; rs17277546, P = 5.8 × 10-14), and CYP11B1/B2 (rs10093796, P = 1.2 × 10-8). E2 signals in CYP19A1 and FAM9B were associated with bone mineral density (BMD). Mendelian randomization analysis suggested a causal effect of serum E2 on BMD in men. A 1 pg/mL genetically increased E2 was associated with a 0.048 standard deviation increase in lumbar spine BMD (P = 2.8 × 10-12). In men and women combined, CYP19A1 alleles associated with higher E2 levels were associated with lower degrees of insulin resistance. Conclusions: Our findings confirm that CYP19A1 is an important genetic regulator of E2 and E1 levels and strengthen the causal importance of E2 for bone health in men. We also report two independent loci on the X-chromosome for E2, and one locus each in TRIM4 and CYP11B1/B2, for E1.


Assuntos
Aromatase/genética , Densidade Óssea/genética , Estradiol/sangue , Densidade Óssea/fisiologia , Cromossomos Humanos X , Estudos de Coortes , Estradiol/genética , Estradiol/fisiologia , Estrona/sangue , Estrona/genética , Feminino , Regulação da Expressão Gênica/fisiologia , Estudo de Associação Genômica Ampla , Genótipo , Hormônios Esteroides Gonadais/sangue , Humanos , Resistência à Insulina/genética , Resistência à Insulina/fisiologia , Vértebras Lombares/fisiologia , Masculino , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Testosterona/sangue
8.
J Clin Endocrinol Metab ; 102(11): 4124-4135, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28938457

RESUMO

Context: Hypertension in young women is uncommon compared with young men and older women. Estrogen appears to protect most women against hypertension, with incidence increasing after menopause. Because some premenopausal women develop hypertension, estrogen may play a different role in these women. Genetic variations in the estrogen receptor (ER) are associated with cardiovascular disease. ER-ß, encoded by ESR2, is the ER predominantly expressed in vascular smooth muscle. Objective: To determine an association of single nucleotide polymorphisms in ESR2 with salt sensitivity of blood pressure (SSBP) and estrogen status in women. Methods: Candidate gene association study with ESR2 and SSBP conducted in normotensive and hypertensive women and men in two cohorts: International Hypertensive Pathotype (HyperPATH) (n = 584) (discovery) and Mexican American Hypertension-Insulin Resistance Study (n = 662) (validation). Single nucleotide polymorphisms in ESR1 (ER-α) were also analyzed. Analysis conducted in younger (<51 years, premenopausal, "estrogen-replete") and older women (≥51 years, postmenopausal, "estrogen-deplete"). Men were analyzed to control for aging. Results: Multivariate analyses of HyperPATH data between variants of ESR2 and SSBP documented that ESR2 rs10144225 minor (risk) allele carriers had a significantly positive association with SSBP driven by estrogen-replete women (ß = +4.4 mm Hg per risk allele, P = 0.004). Findings were confirmed in Hypertension Insulin-Resistance Study premenopausal women. HyperPATH cohort analyses revealed risk allele carriers vs noncarriers had increased aldosterone/renin ratios. No associations were detected with ESR1. Conclusions: The variation at rs10144225 in ESR2 was associated with SSBP in premenopausal women (estrogen-replete) and not in men or postmenopausal women (estrogen-deplete). Inappropriate aldosterone levels on a liberal salt diet may mediate the SSBP.


Assuntos
Receptor beta de Estrogênio/genética , Hipertensão/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Fatores Etários , Idoso , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/genética , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais , Cloreto de Sódio na Dieta/farmacologia , Adulto Jovem
9.
Circ Cardiovasc Genet ; 10(2): e001527, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28348047

RESUMO

BACKGROUND: Genome-wide single marker and gene-based meta-analyses of long-term average (LTA) blood pressure (BP) phenotypes may reveal novel findings for BP. METHODS AND RESULTS: We conducted genome-wide analysis among 18 422 East Asian participants (stage 1) followed by replication study of ≤46 629 participants of European ancestry (stage 2). Significant single-nucleotide polymorphisms and genes were determined by a P<5.0×10-8 and 2.5×10-6, respectively, in joint analyses of stage-1 and stage-2 data. We identified 1 novel ARL3 variant, rs4919669 at 10q24.32, influencing LTA systolic BP (stage-1 P=5.03×10-8, stage-2 P=8.64×10-3, joint P=2.63×10-8) and mean arterial pressure (stage-1 P=3.59×10-9, stage-2 P=2.35×10-2, joint P=2.64×10-8). Three previously reported BP loci (WBP1L, NT5C2, and ATP2B1) were also identified for all BP phenotypes. Gene-based analysis provided the first robust evidence for association of KCNJ11 with LTA systolic BP (stage-1 P=8.55×10-6, stage-2 P=1.62×10-5, joint P=3.28×10-9) and mean arterial pressure (stage-1 P=9.19×10-7, stage-2 P=9.69×10-5, joint P=2.15×10-9) phenotypes. Fourteen genes (TMEM180, ACTR1A, SUFU, ARL3, SFXN2, WBP1L, CYP17A1, C10orf32, C10orf32-ASMT, AS3MT, CNNM2, and NT5C2 at 10q24.32; ATP2B1 at 12q21.33; and NCR3LG1 at 11p15.1) implicated by previous genome-wide association study meta-analyses were also identified. Among the loci identified by the previous genome-wide association study meta-analysis of LTA BP, we transethnically replicated associations of the KCNK3 marker rs1275988 at 2p23.3 with LTA systolic BP and mean arterial pressure phenotypes (P=1.27×10-4 and 3.30×10-4, respectively). CONCLUSIONS: We identified 1 novel variant and 1 novel gene and present the first direct evidence of relevance of the KCNK3 locus for LTA BP among East Asians.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Pressão Sanguínea/genética , Loci Gênicos , Estudo de Associação Genômica Ampla , Fenótipo , Polimorfismo de Nucleotídeo Único , Extremo Oriente , Feminino , Humanos , Masculino
10.
Am J Med Genet A ; 170(10): 2652-61, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27240702

RESUMO

Bent Bone Dysplasia-FGFR2 type is a relatively recently described bent bone phenotype with diagnostic clinical, radiographic, and molecular characteristics. Here we report on 11 individuals, including the original four patients plus seven new individuals with three longer-term survivors. The prenatal phenotype included stillbirth, bending of the femora, and a high incidence of polyhydramnios, prematurity, and perinatal death in three of 11 patients in the series. The survivors presented with characteristic radiographic findings that were observed among those with lethality, including bent bones, distinctive (moustache-shaped) small clavicles, angel-shaped metacarpals and phalanges, poor mineralization of the calvarium, and craniosynostosis. Craniofacial abnormalities, hirsutism, hepatic abnormalities, and genitourinary abnormalities were noted as well. Longer-term survivors all needed ventilator support. Heterozygosity for mutations in the gene that encodes Fibroblast Growth Factor Receptor 2 (FGFR2) was identified in the nine individuals with available DNA. Description of these patients expands the prenatal and postnatal findings of Bent Bone Dysplasia-FGFR2 type and adds to the phenotypic spectrum among all FGFR2 disorders. © 2016 Wiley Periodicals, Inc.


Assuntos
Clavícula/anormalidades , Falanges dos Dedos da Mão/anormalidades , Mutação , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/genética , Fenótipo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Alelos , Substituição de Aminoácidos , Facies , Feminino , Genótipo , Humanos , Masculino , Gravidez , Resultado da Gravidez , Diagnóstico Pré-Natal , Radiografia , Sistema de Registros
11.
Diabetes ; 65(7): 2072-80, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27207554

RESUMO

Type 2 diabetes (T2D) is a heterogeneous disorder with contributions from peripheral insulin resistance and ß-cell dysfunction. For minimization of phenotypic heterogeneity, quantitative intermediate phenotypes characterizing basal glucose homeostasis (insulin resistance and HOMA of insulin resistance [HOMAIR] and of ß-cell function [HOMAB]) have shown promise in relatively large samples. We investigated the utility of dynamic measures of glucose homeostasis (insulin sensitivity [SI] and acute insulin response [AIRg]) evaluating T2D-susceptibility variants (n = 57) in Hispanic Americans from the GUARDIAN Consortium (n = 2,560). Basal and dynamic measures were genetically correlated (HOMAB-AIRg: ρG = 0.28-0.73; HOMAIR-SI: ρG = -0.73 to -0.83) with increased heritability for the dynamic measure AIRg Significant association of variants with dynamic measures (P < 8.77 × 10(-4)) was observed. A pattern of superior performance of AIRg was observed for well-established loci including MTNR1B (P = 9.46 × 10(-12)), KCNQ1 (P = 1.35 × 10(-4)), and TCF7L2 (P = 5.10 × 10(-4)) with study-wise statistical significance. Notably, significant association of MTNR1B with AIRg (P < 1.38 × 10(-9)) was observed in a population one-fourteenth the size of the initial discovery cohort. These observations suggest that basal and dynamic measures provide different views and levels of sensitivity to discrete elements of glucose homeostasis. Although more costly to obtain, dynamic measures yield significant results that could be considered physiologically "closer" to causal pathways and provide insight into the discrete mechanisms of action.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/genética , Resistência à Insulina/fisiologia , Insulina/sangue , Adulto , Idoso , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Teste de Tolerância a Glucose , Homeostase/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
13.
Circ Cardiovasc Genet ; 9(1): 45-54, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26567291

RESUMO

BACKGROUND: There is increasing evidence that retinal microvascular diameters are associated with cardiovascular and cerebrovascular conditions. The shared genetic effects of these associations are currently unknown. The aim of this study was to increase our understanding of the genetic factors that mediate retinal vessel size. METHODS AND RESULTS: This study extends previous genome-wide association study results using 24 000+ multiethnic participants from 7 discovery cohorts and 5000+ subjects of European ancestry from 2 replication cohorts. Using the Illumina HumanExome BeadChip, we investigate the association of single-nucleotide polymorphisms and variants collectively across genes with summary measures of retinal vessel diameters, referred to as the central retinal venule equivalent and the central retinal arteriole equivalent. We report 4 new loci associated with central retinal venule equivalent, one of which is also associated with central retinal arteriole equivalent. The 4 single-nucleotide polymorphisms are rs7926971 in TEAD1 (P=3.1×10(-) (11); minor allele frequency=0.43), rs201259422 in TSPAN10 (P=4.4×10(-9); minor allele frequency=0.27), rs5442 in GNB3 (P=7.0×10(-10); minor allele frequency=0.05), and rs1800407 in OCA2 (P=3.4×10(-8); minor allele frequency=0.05). The latter single-nucleotide polymorphism, rs1800407, was also associated with central retinal arteriole equivalent (P=6.5×10(-12)). Results from the gene-based burden tests were null. In phenotype look-ups, single-nucleotide polymorphism rs201255422 was associated with both systolic (P=0.001) and diastolic blood pressures (P=8.3×10(-04)). CONCLUSIONS: Our study expands the understanding of genetic factors influencing the size of the retinal microvasculature. These findings may also provide insight into the relationship between retinal and systemic microvascular disease.


Assuntos
Proteínas de Ligação a DNA/genética , Loci Gênicos , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único , Artéria Retiniana , Veia Retiniana , Tetraspaninas/genética , Fatores de Transcrição/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Arteríolas , Feminino , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-Idade , Vênulas
14.
PLoS One ; 10(11): e0134649, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26599207

RESUMO

Obesity is growing epidemic affecting 35% of adults in the United States. Previous genome-wide association studies (GWAS) have identified numerous loci associated with obesity. However, the majority of studies have been completed in Caucasians focusing on total body measures of adiposity. Here we report the results from genome-wide and exome chip association studies focusing on total body measures of adiposity including body mass index (BMI), percent body fat (PBF) and measures of fat deposition including waist circumference (WAIST), waist-hip ratio (WHR), subcutaneous adipose tissue (SAT), and visceral adipose tissue (VAT) in Hispanic Americans (nmax = 1263) from the Insulin Resistance Atherosclerosis Family Study (IRASFS). Five SNPs from two novel loci attained genome-wide significance (P<5.00x10-8) in IRASFS. A missense SNP in the isocitrate dehydrogenase 1 gene (IDH1) was associated with WAIST (rs34218846, MAF = 6.8%, PDOM = 1.62x10-8). This protein is postulated to play an important role in fat and cholesterol biosynthesis as demonstrated in cell and knock-out animal models. Four correlated intronic SNPs in the Zinc finger, GRF-type containing 1 gene (ZGRF1; SNP rs1471880, MAF = 48.1%, PDOM = 1.00x10-8) were strongly associated with WHR. The exact biological function of ZGRF1 and the connection with adiposity remains unclear. SNPs with p-values less than 5.00x10-6 from IRASFS were selected for replication. Meta-analysis was computed across seven independent Hispanic-American cohorts (nmax = 4156) and the strongest signal was rs1471880 (PDOM = 8.38x10-6) in ZGRF1 with WAIST. In conclusion, a genome-wide and exome chip association study was conducted that identified two novel loci (IDH1 and ZGRF1) associated with adiposity. While replication efforts were inconclusive, when taken together with the known biology, IDH1 and ZGRF1 warrant further evaluation.


Assuntos
Adiposidade/genética , Hispano-Americanos/genética , Isocitrato Desidrogenase/genética , Proteínas de Membrana/genética , Obesidade/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único
15.
Metabolism ; 64(12): 1674-81, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26475177

RESUMO

CONTEXT AND OBJECTIVE: We examined whether a prevalent caveolin-1 gene (CAV1) variant, previously related to insulin resistance, is associated with metabolic syndrome (MetS). PATIENTS AND METHODS: We included subjects genotyped for the CAV1 variant rs926198 from two cohorts: 735 Caucasians from the HyperPATH multicenter study, and 810 Hispanic participants from the HTN-IR cohort. RESULTS: Minor allele carriers from HyperPATH cohort (57% of subjects) had higher Framingham risk scores, higher odds of diabetes (10.7% vs 5.7%, p=0.016), insulin resistance (44.3% vs 35.1%, p=0.022), low HDL (49.3% vs 39.6%, p=0.018) and MetS (33% vs 20.5%, p<0.001) but similar BMI. Consistently, minor allele carriers exhibited higher odds of MetS, even when adjusted for confounders and relatedness (OR 2.83 (1.73-4.63), p<0.001). The association with MetS was replicated in the Hispanic cohort HTN-IR (OR 1.61, [1.06-2.44], p=0.025). Exploratory analyses suggest that MetS risk is modified by a CAV1 variant-BMI status interaction, whereby the minor allele carrier status strongly predicted MetS (OR 3.86 [2.05-7.27], p<0.001) and diabetes (OR 2.27 [1.07-4.78], p=0.03) in non-obese, but not in obese subjects. In addition, we observed a familial aggregation for MetS diagnosis in minor allele carriers. CONCLUSION: The prevalent CAV1 gene variant rs926198 is associated with MetS in separate Caucasian and Hispanic cohorts. These findings appear to be driven by an interaction between the genetic marker and obesity status, suggesting that the CAV1 variant may improve risk profiling in non-obese subjects. Additional studies are needed to confirm the clinical implications of our results.


Assuntos
Caveolina 1/genética , Grupo com Ancestrais do Continente Europeu/genética , Hispano-Americanos/genética , Síndrome Metabólica/genética , Adulto , Estudos de Coortes , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
16.
J Clin Invest ; 125(4): 1739-51, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25798622

RESUMO

Decreased insulin sensitivity, also referred to as insulin resistance (IR), is a fundamental abnormality in patients with type 2 diabetes and a risk factor for cardiovascular disease. While IR predisposition is heritable, the genetic basis remains largely unknown. The GENEticS of Insulin Sensitivity consortium conducted a genome-wide association study (GWAS) for direct measures of insulin sensitivity, such as euglycemic clamp or insulin suppression test, in 2,764 European individuals, with replication in an additional 2,860 individuals. The presence of a nonsynonymous variant of N-acetyltransferase 2 (NAT2) [rs1208 (803A>G, K268R)] was strongly associated with decreased insulin sensitivity that was independent of BMI. The rs1208 "A" allele was nominally associated with IR-related traits, including increased fasting glucose, hemoglobin A1C, total and LDL cholesterol, triglycerides, and coronary artery disease. NAT2 acetylates arylamine and hydrazine drugs and carcinogens, but predicted acetylator NAT2 phenotypes were not associated with insulin sensitivity. In a murine adipocyte cell line, silencing of NAT2 ortholog Nat1 decreased insulin-mediated glucose uptake, increased basal and isoproterenol-stimulated lipolysis, and decreased adipocyte differentiation, while Nat1 overexpression produced opposite effects. Nat1-deficient mice had elevations in fasting blood glucose, insulin, and triglycerides and decreased insulin sensitivity, as measured by glucose and insulin tolerance tests, with intermediate effects in Nat1 heterozygote mice. Our results support a role for NAT2 in insulin sensitivity.


Assuntos
Arilamina N-Acetiltransferase/fisiologia , Resistência à Insulina/fisiologia , Mutação de Sentido Incorreto , Mutação Puntual , Células 3T3-L1 , Adipogenia/efeitos dos fármacos , Adipogenia/fisiologia , Adolescente , Adulto , Animais , Arilamina N-Acetiltransferase/deficiência , Arilamina N-Acetiltransferase/genética , Grupo com Ancestrais do Continente Asiático/genética , Criança , Doença das Coronárias/enzimologia , Doença das Coronárias/genética , Europa (Continente)/epidemiologia , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Frequência do Gene , Estudo de Associação Genômica Ampla , Glucose/metabolismo , Hemoglobina A Glicada/análise , Hispano-Americanos/genética , Humanos , Hiperglicemia/enzimologia , Hiperglicemia/genética , Hipertrigliceridemia/enzimologia , Hipertrigliceridemia/genética , Isoenzimas/deficiência , Isoenzimas/fisiologia , Lipólise/efeitos dos fármacos , Lipólise/fisiologia , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Taiwan/epidemiologia , Estados Unidos/epidemiologia , Adulto Jovem
17.
Genome Res ; 25(3): 305-15, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25637381

RESUMO

Recommendations for laboratories to report incidental findings from genomic tests have stimulated interest in such results. In order to investigate the criteria and processes for assigning the pathogenicity of specific variants and to estimate the frequency of such incidental findings in patients of European and African ancestry, we classified potentially actionable pathogenic single-nucleotide variants (SNVs) in all 4300 European- and 2203 African-ancestry participants sequenced by the NHLBI Exome Sequencing Project (ESP). We considered 112 gene-disease pairs selected by an expert panel as associated with medically actionable genetic disorders that may be undiagnosed in adults. The resulting classifications were compared to classifications from other clinical and research genetic testing laboratories, as well as with in silico pathogenicity scores. Among European-ancestry participants, 30 of 4300 (0.7%) had a pathogenic SNV and six (0.1%) had a disruptive variant that was expected to be pathogenic, whereas 52 (1.2%) had likely pathogenic SNVs. For African-ancestry participants, six of 2203 (0.3%) had a pathogenic SNV and six (0.3%) had an expected pathogenic disruptive variant, whereas 13 (0.6%) had likely pathogenic SNVs. Genomic Evolutionary Rate Profiling mammalian conservation score and the Combined Annotation Dependent Depletion summary score of conservation, substitution, regulation, and other evidence were compared across pathogenicity assignments and appear to have utility in variant classification. This work provides a refined estimate of the burden of adult onset, medically actionable incidental findings expected from exome sequencing, highlights challenges in variant classification, and demonstrates the need for a better curated variant interpretation knowledge base.


Assuntos
Exoma , Genômica , Achados Incidentais , Adulto , Grupo com Ancestrais do Continente Africano/genética , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Frequência do Gene , Genes Dominantes , Estudos de Associação Genética , Testes Genéticos , Genoma Humano , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único
18.
Environ Health Perspect ; 123(2): 144-51, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25302408

RESUMO

BACKGROUND: Air pollution is linked to low lung function and to respiratory events, yet little is known of associations with lung structure. OBJECTIVES: We examined associations of particulate matter (PM2.5, PM10) and nitrogen oxides (NOx) with percent emphysema-like lung on computed tomography (CT). METHODS: The Multi-Ethnic Study of Atherosclerosis (MESA) recruited participants (45-84 years of age) in six U.S. states. Percent emphysema was defined as lung regions < -910 Hounsfield Units on cardiac CT scans acquired following a highly standardized protocol. Spirometry was also conducted on a subset. Individual-level 1- and 20-year average air pollution exposures were estimated using spatiotemporal models that included cohort-specific measurements. Multivariable regression was conducted to adjust for traditional risk factors and study location. RESULTS: Among 6,515 participants, we found evidence of an association between percent emphysema and long-term pollution concentrations in an analysis leveraging between-city exposure contrasts. Higher concentrations of PM2.5 (5 µg/m3) and NOx (25 ppb) over the previous year were associated with 0.6 (95% CI: 0.1, 1.2%) and 0.5 (95% CI: 0.1, 0.9%) higher average percent emphysema, respectively. However, after adjustment for study site the associations were -0.6% (95% CI: -1.5, 0.3%) for PM2.5 and -0.5% (95% CI: -1.1, 0.02%) for NOx. Lower lung function measures (FEV1 and FVC) were associated with higher PM2.5 and NOx levels in 3,791 participants before and after adjustment for study site, though most associations were not statistically significant. CONCLUSIONS: Associations between ambient air pollution and percentage of emphysema-like lung were inconclusive in this cross-sectional study, thus longitudinal analyses may better clarify these associations with percent emphysema.


Assuntos
Poluição do Ar/estatística & dados numéricos , Enfisema/epidemiologia , Óxidos de Nitrogênio/efeitos adversos , Material Particulado/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Poluição do Ar/efeitos adversos , Estudos Transversais , Enfisema/induzido quimicamente , Exposição Ambiental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Óxidos de Nitrogênio/análise , Material Particulado/análise , Espirometria , Tomografia Computadorizada por Raios X , Estados Unidos
19.
Diabetes ; 64(5): 1853-66, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25524916

RESUMO

Insulin sensitivity, insulin secretion, insulin clearance, and glucose effectiveness exhibit strong genetic components, although few studies have examined their genetic architecture or influence on type 2 diabetes (T2D) risk. We hypothesized that loci affecting variation in these quantitative traits influence T2D. We completed a multicohort genome-wide association study to search for loci influencing T2D-related quantitative traits in 4,176 Mexican Americans. Quantitative traits were measured by the frequently sampled intravenous glucose tolerance test (four cohorts) or euglycemic clamp (three cohorts), and random-effects models were used to test the association between loci and quantitative traits, adjusting for age, sex, and admixture proportions (Discovery). Analysis revealed a significant (P < 5.00 × 10(-8)) association at 11q14.3 (MTNR1B) with acute insulin response. Loci with P < 0.0001 among the quantitative traits were examined for translation to T2D risk in 6,463 T2D case and 9,232 control subjects of Mexican ancestry (Translation). Nonparametric meta-analysis of the Discovery and Translation cohorts identified significant associations at 6p24 (SLC35B3/TFAP2A) with glucose effectiveness/T2D, 11p15 (KCNQ1) with disposition index/T2D, and 6p22 (CDKAL1) and 11q14 (MTNR1B) with acute insulin response/T2D. These results suggest that T2D and insulin secretion and sensitivity have both shared and distinct genetic factors, potentially delineating genomic components of these quantitative traits that drive the risk for T2D.


Assuntos
Glicemia/genética , Diabetes Mellitus Tipo 2/metabolismo , Variação Genética , Homeostase/fisiologia , Glicemia/metabolismo , Bases de Dados Factuais , Diabetes Mellitus Tipo 2/etnologia , Regulação da Expressão Gênica/fisiologia , Genoma , Estudo de Associação Genômica Ampla , Genótipo , Hispano-Americanos , Homeostase/genética , Humanos
20.
PLoS One ; 9(9): e107110, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25233373

RESUMO

Refractive error (RE) is a complex, multifactorial disorder characterized by a mismatch between the optical power of the eye and its axial length that causes object images to be focused off the retina. The two major subtypes of RE are myopia (nearsightedness) and hyperopia (farsightedness), which represent opposite ends of the distribution of the quantitative measure of spherical refraction. We performed a fixed effects meta-analysis of genome-wide association results of myopia and hyperopia from 9 studies of European-derived populations: AREDS, KORA, FES, OGP-Talana, MESA, RSI, RSII, RSIII and ERF. One genome-wide significant region was observed for myopia, corresponding to a previously identified myopia locus on 8q12 (p = 1.25×10(-8)), which has been reported by Kiefer et al. as significantly associated with myopia age at onset and Verhoeven et al. as significantly associated to mean spherical-equivalent (MSE) refractive error. We observed two genome-wide significant associations with hyperopia. These regions overlapped with loci on 15q14 (minimum p value = 9.11×10(-11)) and 8q12 (minimum p value 1.82×10(-11)) previously reported for MSE and myopia age at onset. We also used an intermarker linkage- disequilibrium-based method for calculating the effective number of tests in targeted regional replication analyses. We analyzed myopia (which represents the closest phenotype in our data to the one used by Kiefer et al.) and showed replication of 10 additional loci associated with myopia previously reported by Kiefer et al. This is the first replication of these loci using myopia as the trait under analysis. "Replication-level" association was also seen between hyperopia and 12 of Kiefer et al.'s published loci. For the loci that show evidence of association to both myopia and hyperopia, the estimated effect of the risk alleles were in opposite directions for the two traits. This suggests that these loci are important contributors to variation of refractive error across the distribution.


Assuntos
Olho/fisiopatologia , Hiperopia/genética , Miopia/genética , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Alelos , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Estudos de Associação Genética , Marcadores Genéticos/genética , Predisposição Genética para Doença , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...