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Zari Dastani,
Marie-France Hivert,
Nicholas Timpson,
John R B Perry,
Xin Yuan,
Robert A Scott,
Peter Henneman,
Iris M Heid,
Jorge R Kizer,
Leo-Pekka Lyytikäinen, [......],
Eric E Schadt,
David P Strachan,
Muredach P Reilly,
Nilesh J Samani,
Heribert Schunkert,
L Adrienne Cupples,
Manjinder S Sandhu,
Paul M Ridker,
Daniel J Rader,
Sekar Kathiresan
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ABSTRACT: Circulating levels of adiponectin, a hormone produced predominantly by adipocytes, are highly heritable and are inversely associated with type 2 diabetes mellitus (T2D) and other metabolic traits. We conducted a meta-analysis of genome-wide association studies in 39,883 individuals of European ancestry to identify genes associated with metabolic disease. We identified 8 novel loci associated with adiponectin levels and confirmed 2 previously reported loci (P = 4.5×10(-8)-1.2×10(-43)). Using a novel method to combine data across ethnicities (N = 4,232 African Americans, N = 1,776 Asians, and N = 29,347 Europeans), we identified two additional novel loci. Expression analyses of 436 human adipocyte samples revealed that mRNA levels of 18 genes at candidate regions were associated with adiponectin concentrations after accounting for multiple testing (p<3×10(-4)). We next developed a multi-SNP genotypic risk score to test the association of adiponectin decreasing risk alleles on metabolic traits and diseases using consortia-level meta-analytic data. This risk score was associated with increased risk of T2D (p = 4.3×10(-3), n = 22,044), increased triglycerides (p = 2.6×10(-14), n = 93,440), increased waist-to-hip ratio (p = 1.8×10(-5), n = 77,167), increased glucose two hours post oral glucose tolerance testing (p = 4.4×10(-3), n = 15,234), increased fasting insulin (p = 0.015, n = 48,238), but with lower in HDL-cholesterol concentrations (p = 4.5×10(-13), n = 96,748) and decreased BMI (p = 1.4×10(-4), n = 121,335). These findings identify novel genetic determinants of adiponectin levels, which, taken together, influence risk of T2D and markers of insulin resistance.
PLoS Genetics 03/2012; 8(3):e1002607. · 8.69 Impact Factor
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Nicholette D Palmer,
Caitrin W McDonough,
Pamela J Hicks,
Bong H Roh,
Maria R Wing,
S Sandy An,
Jessica M Hester,
Jessica N Cooke,
Meredith A Bostrom,
Megan E Rudock, [......],
Angelo Scuteri,
David Schlessinger,
Manuela Uda,
Aimo Ruokonen,
Marjo-Riitta Jarvelin,
Dawn M Waterworth,
Peter Vollenweider,
Leena Peltonen,
Vincent Mooser,
Robert Sladek
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ABSTRACT: African Americans are disproportionately affected by type 2 diabetes (T2DM) yet few studies have examined T2DM using genome-wide association approaches in this ethnicity. The aim of this study was to identify genes associated with T2DM in the African American population. We performed a Genome Wide Association Study (GWAS) using the Affymetrix 6.0 array in 965 African-American cases with T2DM and end-stage renal disease (T2DM-ESRD) and 1029 population-based controls. The most significant SNPs (n = 550 independent loci) were genotyped in a replication cohort and 122 SNPs (n = 98 independent loci) were further tested through genotyping three additional validation cohorts followed by meta-analysis in all five cohorts totaling 3,132 cases and 3,317 controls. Twelve SNPs had evidence of association in the GWAS (P<0.0071), were directionally consistent in the Replication cohort and were associated with T2DM in subjects without nephropathy (P<0.05). Meta-analysis in all cases and controls revealed a single SNP reaching genome-wide significance (P<2.5×10(-8)). SNP rs7560163 (P = 7.0×10(-9), OR (95% CI) = 0.75 (0.67-0.84)) is located intergenically between RND3 and RBM43. Four additional loci (rs7542900, rs4659485, rs2722769 and rs7107217) were associated with T2DM (P<0.05) and reached more nominal levels of significance (P<2.5×10(-5)) in the overall analysis and may represent novel loci that contribute to T2DM. We have identified novel T2DM-susceptibility variants in the African-American population. Notably, T2DM risk was associated with the major allele and implies an interesting genetic architecture in this population. These results suggest that multiple loci underlie T2DM susceptibility in the African-American population and that these loci are distinct from those identified in other ethnic populations.
PLoS ONE 01/2012; 7(1):e29202. · 4.09 Impact Factor
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Rona J Strawbridge,
Josée Dupuis,
Inga Prokopenko,
Adam Barker,
Emma Ahlqvist,
Denis Rybin,
John R Petrie,
Mary E Travers,
Nabila Bouatia-Naji,
Antigone S Dimas, [......],
Anna L Gloyn,
George V Dedoussis,
Valeriya Lyssenko,
James B Meigs,
Inês Barroso,
Richard M Watanabe,
Erik Ingelsson,
Claudia Langenberg,
Anders Hamsten,
Jose C Florez
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ABSTRACT: Proinsulin is a precursor of mature insulin and C-peptide. Higher circulating proinsulin levels are associated with impaired β-cell function, raised glucose levels, insulin resistance, and type 2 diabetes (T2D). Studies of the insulin processing pathway could provide new insights about T2D pathophysiology.
We have conducted a meta-analysis of genome-wide association tests of ∼2.5 million genotyped or imputed single nucleotide polymorphisms (SNPs) and fasting proinsulin levels in 10,701 nondiabetic adults of European ancestry, with follow-up of 23 loci in up to 16,378 individuals, using additive genetic models adjusted for age, sex, fasting insulin, and study-specific covariates.
Nine SNPs at eight loci were associated with proinsulin levels (P < 5 × 10(-8)). Two loci (LARP6 and SGSM2) have not been previously related to metabolic traits, one (MADD) has been associated with fasting glucose, one (PCSK1) has been implicated in obesity, and four (TCF7L2, SLC30A8, VPS13C/C2CD4A/B, and ARAP1, formerly CENTD2) increase T2D risk. The proinsulin-raising allele of ARAP1 was associated with a lower fasting glucose (P = 1.7 × 10(-4)), improved β-cell function (P = 1.1 × 10(-5)), and lower risk of T2D (odds ratio 0.88; P = 7.8 × 10(-6)). Notably, PCSK1 encodes the protein prohormone convertase 1/3, the first enzyme in the insulin processing pathway. A genotype score composed of the nine proinsulin-raising alleles was not associated with coronary disease in two large case-control datasets.
We have identified nine genetic variants associated with fasting proinsulin. Our findings illuminate the biology underlying glucose homeostasis and T2D development in humans and argue against a direct role of proinsulin in coronary artery disease pathogenesis.
Diabetes 08/2011; 60(10):2624-34. · 8.29 Impact Factor
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Nicole Soranzo,
Serena Sanna,
Eleanor Wheeler,
Christian Gieger,
Dörte Radke,
Josée Dupuis,
Nabila Bouatia-Naji,
Claudia Langenberg,
Inga Prokopenko,
Elliot Stolerman, [......],
Michael Boehnke,
Philippe Froguel,
Leif Groop,
Mark I McCarthy,
W H Linda Kao,
Jose C Florez,
Manuela Uda,
Nicholas J Wareham,
Inês Barroso,
James B Meigs
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ABSTRACT: 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.
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.
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 × 10⁻²⁰), 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 × 10⁻²⁰) 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).
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).
Diabetes 12/2010; 59(12):3229-39. · 8.29 Impact Factor
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Josée Dupuis,
Claudia Langenberg,
Inga Prokopenko,
Richa Saxena,
Nicole Soranzo,
Anne U Jackson,
Eleanor Wheeler,
Nicole L Glazer,
Nabila Bouatia-Naji,
Anna L Gloyn, [......],
Nicholas J Wareham,
Robert Sladek,
Philippe Froguel,
Richard M Watanabe,
James B Meigs,
Leif Groop,
Michael Boehnke,
Mark I McCarthy,
Jose C Florez,
Inês Barroso
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ABSTRACT: Levels of circulating glucose are tightly regulated. To identify new loci influencing glycemic traits, we performed meta-analyses of 21 genome-wide association studies informative for fasting glucose, fasting insulin and indices of beta-cell function (HOMA-B) and insulin resistance (HOMA-IR) in up to 46,186 nondiabetic participants. Follow-up of 25 loci in up to 76,558 additional subjects identified 16 loci associated with fasting glucose and HOMA-B and two loci associated with fasting insulin and HOMA-IR. These include nine loci newly associated with fasting glucose (in or near ADCY5, MADD, ADRA2A, CRY2, FADS1, GLIS3, SLC2A2, PROX1 and C2CD4B) and one influencing fasting insulin and HOMA-IR (near IGF1). We also demonstrated association of ADCY5, PROX1, GCK, GCKR and DGKB-TMEM195 with type 2 diabetes. Within these loci, likely biological candidate genes influence signal transduction, cell proliferation, development, glucose-sensing and circadian regulation. Our results demonstrate that genetic studies of glycemic traits can identify type 2 diabetes risk loci, as well as loci containing gene variants that are associated with a modest elevation in glucose levels but are not associated with overt diabetes.
Nature Genetics 02/2010; 42(2):105-16. · 35.53 Impact Factor
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Javier Gayán,
José J Galan,
Antonio González-Pérez,
María Eugenia Sáez, María Teresa Martínez-Larrad,
Carina Zabena,
M Carmen Rivero,
Ana Salinas,
Reposo Ramírez-Lorca,
Francisco J Morón, [......],
María Dolores Ochoa,
Marta Gutiérrez,
Mercedes Reina,
Rocío Pascual,
Alejandro Romo-Astorga,
Juan Luis Susillo-González,
Enrique Vázquez,
Luis M Real,
Agustín Ruiz,
Manuel Serrano-Ríos
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ABSTRACT: Genetic admixture is a common caveat for genetic association analysis. Therefore, it is important to characterize the genetic structure of the population under study to control for this kind of potential bias.
In this study we have sampled over 800 unrelated individuals from the population of Spain, and have genotyped them with a genome-wide coverage. We have carried out linkage disequilibrium, haplotype, population structure and copy-number variation (CNV) analyses, and have compared these estimates of the Spanish population with existing data from similar efforts.
In general, the Spanish population is similar to the Western and Northern Europeans, but has a more diverse haplotypic structure. Moreover, the Spanish population is also largely homogeneous within itself, although patterns of micro-structure may be able to predict locations of origin from distant regions. Finally, we also present the first characterization of a CNV map of the Spanish population. These results and original data are made available to the scientific community.
BMC Genomics 01/2010; 11:326. · 4.07 Impact Factor
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ABSTRACT: C-reactive protein (CRP) is a marker of systemic inflammation significantly associated with an increased risk of cardiovascular disease in the general population. The aim of our current work was to study those clinical and genetic variables potentially associated with interindividual variability in serum CRP levels. A random sample of 844 participants (450 women, mean age 55 years) from a study carried out on the general Spanish population (The Segovia Study) was studied. Our results showed that age, gender, waist circumference, leptin, impaired glucose tolerance and smoking were the clinical variables significantly associated with variations in serum CRP levels. Among those, leptin showed the strongest association, explaining 11% of the interindividual variability in circulating CRP levels (p<0.001). To study the effect of genetic variants on serum CRP levels, 10 SNPs within the CRP locus were genotyped in 756 participants. Four of these SNPs (rs1417938, rs1800947, rs1130864, rs1205) were significantly associated with CRP levels after adjustment for clinical variables. Among the common haplotypes inferred from eight SNPs, two (CCATGCCT, p=0.025; CTATCCTT, p=0.004) explained 2.9% of the total variation in serum CRP. The results here reported show that 2.9% of the total variation in circulating CRP levels seems to be explained by genetics variations within CRP locus. Furthermore, serum leptin levels are strongly associated with serum CRP levels in our Spanish population.
Thrombosis and Haemostasis 11/2007; 98(5):1088-95. · 5.04 Impact Factor
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ABSTRACT: Lipodystrophy (lipo) and metabolic derangements associated with an increased cardiovascular risk are observed frequently in human immunodeficiency virus (HIV)-infected patients who receive antiretroviral treatment (ART). The objective of the study was to provide detailed biochemical information about metabolic syndrome in this condition. One hundred forty-six HIV-infected male and female patients on ART for more than 6 months were compared with 156 body mass index (BMI)-matched healthy subjects. Lipodystrophy was diagnosed upon patient and physician concordance. Metabolic syndrome was defined according to the Adult Treatment Panel III criteria. Plasma adiponectin (AD) and leptin were measured by radioimmunoassay. Insulin resistance (IR) was assessed by the homeostasis model assessment (HOMA). The prevalence of metabolic syndrome was higher in HIV-infected patients on ART than in non-HIV-infected healthy controls (15.8% vs 3.2%; P < .001). Patients with metabolic syndrome are older (44.6 +/- 6 vs 39.8 +/- 8 years; P = .004), have an increased BMI (24.9 +/- 3.8 vs 22.9 +/- 9.8 kg/m(2); P = .01), present with a reduced AD-to-leptin ratio log(10) (-0.19 +/- 0.4 vs 0.5 +/- 0.4; P = .04), and show increased IR (HOMA, 5.6 +/- 2.7 vs 3.8 +/- 2.2; P = .001; plasma fasting insulin, 22.9 +/- 9.8 vs 16.6 +/- 9.7 ng/mL; P < .001). In multivariate analysis, the diagnosis of lipo and HOMA were independently and significantly related to metabolic syndrome. In conclusion, the prevalence of metabolic syndrome is significantly increased in HIV-infected patients on ART and its presence is associated with lipo, increased age and BMI, IR, and a reduced plasma AD-to-leptin ratio.
Metabolism 07/2006; 55(7):940-5. · 2.66 Impact Factor
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ABSTRACT: We aimed to estimate the prevalence of the Metabolic Syndrome (MS) in rural and urban areas of the Province of Segovia, Spain, according to the ATPIII criteria (National Cholesterol Education Program's Adults Treatment Panel III report) modified.
Cross-sectional design. Randomized and representative sample of 809 individuals (46% males) aged 35-74 years. Residents in urban and rural areas of the Province of Segovia (Spain). Period of study from January 2000 to January 2003.
The age/sex standardized prevalence of the MS was 17%; 15.7% in males and 18.1% in females. No significant differences in MS prevalence between rural and urban areas were found. The most frequent combination of individual components of MS was abdominal obesity, hyperglycemia and arterial hypertension in males and females. MS was associated with age and obesity in an adjusted logistic regression model. In a second model, abdominal obesity was more common in those individuals with a BMI over 30 kg/m2, secondary education level, age over 45 years, and in female residents in rural areas.
The sex/age adjusted prevalence was lower than that reported in other studies using the ATPIII criteria in Spain. Abdominal obesity was the most frequent single component of MS in females whereas it was arterial hypertension in males.
Medicina Clínica 11/2005; 125(13):481-6. · 1.38 Impact Factor
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ABSTRACT: To determine whether there are variations in leptin levels according to the beta(3)-adrenoceptor (beta(3)-AR) Trp64Arg and uncoupling protein 1 (UCP1) -3826A-->G polymorphisms, given the regulatory role of catecholamines through the beta(3)-AR in leptin production and the previously reported association of the UCP1 -3826A-->G variant with obesity. A total of 160 men and 172 women randomly chosen from a nationwide population-based obesity cross-sectional survey in Spain were studied. Body mass index (BMI), waist-to-hip ratio (WHR), leptin, insulin, fasting and 2-hour post-glucose load glycemia, high-density lipoprotein (HDL)-, low-density lipoprotein (LDL)-, and total cholesterol, and triglyceride plasma levels were measured. beta(3)-AR Trp64Arg and UCP1 -3826A-->G genotypes were determined by restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR). UCP1 -3826G allele frequency was higher in men than in women (0.31 v 0.22, P = .015) and in obese women than in non-obese women (0.31 v 0.17, P = .008). Women carriers of the Arg64 or the alleles also showed higher leptin levels than noncarriers. Multiple linear regression analysis showed that the Arg64 allele is associated with higher leptin levels after the adjustment for gender, age, WHR, and the degree of glucose tolerance. In conclusion, the beta(3)-AR Trp64Arg polymorphism might have an impact on the mechanisms involved in leptin release from adipose tissue. Furthermore, our results agree with the previously reported association between UCP1 -3826G allele and obesity and point to a gender-related effect.
Metabolism 11/2004; 53(11):1411-6. · 2.66 Impact Factor
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ABSTRACT: To investigate the effect of the K121Q plasma cell membrane glycoprotein (PC-1) polymorphism on the components of the insulin resistance syndrome in a population-based nationwide multicenter study in Spain.
The subjects of the study were 293 nonrelated adults (44.7% men and 55.3% women) ages 35 to 64 years randomly chosen from a nationwide population-based survey on obesity and related conditions, including insulin resistance and cardiovascular risk factors. Obesity-related anthropometric measurements included blood pressure, oral glucose tolerance test, lipid profile (total cholesterol, high-density lipoprotein- and low-density lipoprotein-cholesterol, and triglycerides), plasma leptin, insulin levels by radioimmunoassay, and insulin resistance (homeostasis model assessment). K121Q PC-1 genotypes were determined by restriction fragment-length polymorphism-polymerase chain reaction.
Overall Q allele frequency was 0.14, with no differences between obese and nonobese individuals (0.15 vs. 0.13). After adjustment for sex, age, BMI, and degree of glucose tolerance, the Q allele was associated with high plasma leptin and triglyceride levels, but not with insulin resistance.
The results showed that the K121Q PC-1 polymorphism in the Spanish population has no significant impact on insulin sensitivity.
Obesity research 06/2003; 11(5):603-5. · 4.95 Impact Factor
