Time filter

Source Type

Verhaaren B.F.J.,University of Texas Health Science Center at Houston | Smith J.A.,Medical Informatics | Ikram M.K.,Internal Medicine | Adams H.H.,Clinical Chemistry | And 81 more authors.
Circulation: Cardiovascular Genetics | Year: 2015

Background-The burden of cerebral white matter hyperintensities (WMH) is associated with an increased risk of stroke, dementia, and death. WMH are highly heritable, but their genetic underpinnings are incompletely characterized. To identify novel genetic variants influencing WMH burden, we conducted a meta-analysis of multiethnic genome-wide association studies. Methods and Results-We included 21 079 middle-aged to elderly individuals from 29 population-based cohorts, who were free of dementia and stroke and were of European (n=17 936), African (n=1943), Hispanic (n=795), and Asian (n=405) descent. WMH burden was quantified on MRI either by a validated automated segmentation method or a validated visual grading scale. Genotype data in each study were imputed to the 1000 Genomes reference. Within each ethnic group, we investigated the relationship between each single-nucleotide polymorphism and WMH burden using a linear regression model adjusted for age, sex, intracranial volume, and principal components of ancestry. A meta-analysis was conducted for each ethnicity separately and for the combined sample. In the European descent samples, we confirmed a previously known locus on chr17q25 (P=2.7×10-19) and identified novel loci on chr10q24 (P=1.6×10-9) and chr2p21 (P=4.4×10-8). In the multiethnic meta-analysis, we identified 2 additional loci, on chr1q22 (P=2.0×10-8) and chr2p16 (P=1.5×10-8). The novel loci contained genes that have been implicated in Alzheimer disease (chr2p21 and chr10q24), intracerebral hemorrhage (chr1q22), neuroinflammatory diseases (chr2p21), and glioma (chr10q24 and chr2p16). Conclusions-We identified 4 novel genetic loci that implicate inflammatory and glial proliferative pathways in the development of WMH in addition to previously proposed ischemic mechanisms. © 2015 American Heart Association, Inc.

Repapi E.,University of Leicester | Sayers I.,University of Nottingham | Wain L.V.,University of Leicester | Burton P.R.,University of Leicester | And 110 more authors.
Nature Genetics | Year: 2010

Pulmonary function measures are heritable traits that predict morbidity and mortality and define chronic obstructive pulmonary disease (COPD). We tested genome-wide association with forced expiratory volume in 1 s (FEV 1) and the ratio of FEV 1 to forced vital capacity (FVC) in the SpiroMeta consortium (n = 20,288 individuals of European ancestry). We conducted a meta-analysis of top signals with data from direct genotyping (n <32,184 additional individuals) and in silico summary association data from the CHARGE Consortium (n = 21,209) and the Health 2000 survey (n <883). We confirmed the reported locus at 4q31 and identified associations with FEV 1 or FEV 1 /FVC and common variants at five additional loci: 2q35 in TNS1 (P = 1.11 × 10 -12), 4q24 in GSTCD (2.18 × 10 -23), 5q33 in HTR4 (P = 4.29 × 10 -9), 6p21 in AGER (P = 3.07 × 10 -15) and 15q23 in THSD4 (P = 7.24 × 10 -15). mRNA analyses showed expression of TNS1, GSTCD, AGER, HTR4 and THSD4 in human lung tissue. These associations offer mechanistic insight into pulmonary function regulation and indicate potential targets for interventions to alleviate respiratory disease. © 2010 Nature America, Inc. All rights reserved.

Lieb W.,Framingham Heart Study | Lieb W.,University of Kiel | Chen M.-H.,Framingham Heart Study | Larson M.G.,Framingham Heart Study | And 14 more authors.
Circulation: Cardiovascular Genetics | Year: 2015

Background-Endothelial growth factors including angiopoietin-2 (Ang-2), its soluble receptor Tie-2 (sTie-2), and hepatocyte growth factor play important roles in angiogenesis, vascular remodeling, local tumor growth, and metastatic potential of various cancers. Circulating levels of these biomarkers have a heritable component (between 13% and 56%), but the underlying genetic variation influencing these biomarker levels is largely unknown. Methods and Results-We performed a genome-wide association study for circulating Ang-2, sTie-2, and hepatocyte growth factor in 3571 Framingham Heart Study participants and assessed replication of the top hits for Ang-2 and sTie-2 in 3184 participants of the Study of Health in Pomerania. In multivariable-adjusted models, sTie-2 and hepatocyte growth factor concentrations were associated with single-nucleotide polymorphisms in the genes encoding the respective biomarkers (top P=2.40×10-65 [rs2273720] and 3.64×10-19 [rs5745687], respectively). Likewise, rs2442517 in the MCPH1 gene (in which the Ang-2 gene is embedded) was associated with Ang-2 levels (P=5.05×10-8 in Framingham Heart Study and 8.39×10-5 in Study of Health in Pomerania). Furthermore, single-nucleotide polymorphisms in the AB0 gene were associated with sTie-2 (top single-nucleotide polymorphism rs8176693 with P=1.84×10-33 in Framingham Heart Study; P=2.53×10-30 in Study of Health in Pomerania) and Ang-2 (rs8176746 with P=2.07×10-8 in Framingham Heart Study; P=0.001 in Study of Health in Pomerania) levels on a genome-wide significant level. The top genetic loci were explained between 1.7% (Ang-2) and 11.2% (sTie-2) of the interindividual variation in biomarker levels. Conclusions-Genetic variation contributes to the interindividual variation in growth factor levels and explains a modest proportion of circulating hepatocyte growth factor, Ang-2, and Tie-2. This may potentially contribute to the familial susceptibility to cancer, a premise that warrants further studies. © 2015 American Heart Association, Inc.

Haring R.,Institute of Clinical Chemistry and Laboratory Medicine | Wallaschofski H.,Institute of Clinical Chemistry and Laboratory Medicine | Teumer A.,Interfaculty Institute for Genetics and Functional Genomics | Kroemer H.,University of Greifswald | And 6 more authors.
Journal of Molecular Endocrinology | Year: 2013

DHEA is the major precursor of human sex steroid synthesis and is inactivated via sulfonation to DHEAS. A previous genome-wide association study related the single nucleotide polymorphism (SNP) rs2637125, located near the coding region of DHEA sulfotransferase, SULT2A1, to serum DHEAS concentrations. However, the functional relevance of this SNP with regard to DHEA sulfonation is unknown. Using data from 3300 participants of the population-based cohort Study of Health in Pomerania, we identified 43 individuals being homozygote for the minor allele of the SNP rs2637125 (AA) and selected two sex- and age-matched individuals with AG and GG genotype (nZ172) respectively. Steroid analysis including measurement of serum DHEA and DHEAS was carried out by liquid chromatography/mass spectrometry, employing steroid oxime analysis for enhancing the sensitivity of DHEA detection. We applied quantile regression models to compare median hormone levels across SULT2A1 genotypes. Median comparisons by SULT2A1 genotype (AA vs AG and GG genotypes respectively) showed no differences inthe considered hormones including DHEAS, DHEA, androstenedione, as well as cortisol and cortisone concentrations. SULT2A1 genotype also had no effect on the DHEA/DHEAS ratio. Sex-stratified analyses, as well as alternative use of the SULT2A1 SNP rs182420, yielded similar negative results. Genetic variants of SULT2A1 do not appear to have an effect on individual DHEA and DHEAS concentrations or the DHEA/DHEAS ratio as a marker of DHEA sulfonation capacity. © 2013 Society for Endocrinology.

PubMed | Institute of Clinical Chemistry and Laboratory Medicine, University of Greifswald, Interfaculty Institute for Genetics and Functional Genomics and Charité - Medical University of Berlin
Type: Journal Article | Journal: European thyroid journal | Year: 2015

3,5-Diiodo-L-thyronine (3,5-T2) is a thyroid hormone metabolite which exhibited versatile effects in rodent models, including the prevention of insulin resistance or hepatic steatosis typically forced by a high-fat diet. With respect to euthyroid humans, we recently observed a putative link between serum 3,5-T2 and glucose but not lipid metabolism.The aim of the present study was to widely screen the urine metabolome for associations with serum 3,5-T2 concentrations in healthy individuals.Urine metabolites of 715 euthyroid participants of the population-based Study of Health in Pomerania (SHIP-TREND) were analyzed by (1)H-NMR spectroscopy. Multinomial logistic and multivariate linear regression models were used to detect associations between urine metabolites and serum 3,5-T2 concentrations.Serum 3,5-T2 concentrations were positively associated with urinary levels of trigonelline, pyroglutamate, acetone and hippurate. In detail, the odds for intermediate or suppressed serum 3,5-T2 concentrations doubled owing to a 1-standard deviation (SD) decrease in urine trigonelline levels, or increased by 29-50% in relation to a 1-SD decrease in urine pyroglutamate, acetone and hippurate levels.Our findings in humans confirmed the metabolic effects of circulating 3,5-T2 on glucose and lipid metabolism, oxidative stress and enhanced drug metabolism as postulated before based on interventional pharmacological studies in rodents. Of note, 3,5-T2 exhibited a unique urinary metabolic profile distinct from previously published results for the classical thyroid hormones.

PubMed | Stockholm School of Economics, Karolinska Institutet, Queensland Institute of Medical Research Berghofer Medical Research Institute, University of Queensland and 10 more.
Type: Journal Article | Journal: Psychological science | Year: 2014

A recent genome-wide-association study of educational attainment identified three single-nucleotide polymorphisms (SNPs) whose associations, despite their small effect sizes (each R (2) 0.02%), reached genome-wide significance (p < 5 10(-8)) in a large discovery sample and were replicated in an independent sample (p < .05). The study also reported associations between educational attainment and indices of SNPs called polygenic scores. In three studies, we evaluated the robustness of these findings. Study 1 showed that the associations with all three SNPs were replicated in another large (N = 34,428) independent sample. We also found that the scores remained predictive (R (2) 2%) in regressions with stringent controls for stratification (Study 2) and in new within-family analyses (Study 3). Our results show that large and therefore well-powered genome-wide-association studies can identify replicable genetic associations with behavioral traits. The small effect sizes of individual SNPs are likely to be a major contributing factor explaining the striking contrast between our results and the disappointing replication record of most candidate-gene studies.

PubMed | University of Greifswald, Interfaculty Institute for Genetics and Functional Genomics, University of Duisburg - Essen, University of Lübeck and Institute for Clinical Chemistry and Laboratory Medicine
Type: Journal Article | Journal: European thyroid journal | Year: 2015

Hyperthyroidism is known to induce a hypercoagulable state. It stimulates plasma levels of procoagulative factors and reduces fibrinolytic activity. So far most of the data have been derived from patients with endogenous hyperthyroidism with a wide variability in the underlying pathogenesis and severity of the disease.In this study we experimentally induced thyrotoxicosis in healthy volunteers to explore the effects of thyroxine excess on the plasma proteome. Using a shotgun proteomics approach, the abundance of plasma proteins was monitored before, during and after thyrotoxicosis.Sixteen healthy male subjects were sampled at baseline, 4 and 8 weeks under 250 g/day thyroxine p.o., as well as 4 and 8 weeks after stopping the application. Plasma proteins were analyzed after depletion of 6 high-abundance proteins (MARS6) by LC-ESI-MS/MS mass spectrometry. Mass spectrometric raw data were processed using a label-free, intensity-based workflow. Subsequently, the linear dependence between protein abundances and fT4 levels were calculated using a Pearson correlation.All subjects developed biochemical thyrotoxicosis, and this effect was reversed within the first 4 weeks of follow-up. None of the volunteers noticed any subjective symptoms. Levels of 10 proteins involved in the coagulation cascade specifically correlated with fT4, supporting an influence of thyroid hormone levels on blood coagulation even at nonpathological levels.The results suggest that experimental thyrotoxicosis exerts selective and specific thyroxine-induced effects on coagulation markers. Our study design allows assessment of thyroid hormone effects on plasma protein levels without secondary effects of other diseases or therapies.

Loading Interfaculty Institute for Genetics and Functional Genomics collaborators
Loading Interfaculty Institute for Genetics and Functional Genomics collaborators