Genome Wide Meta-analysis Highlights the Role of Genetic Variation in RARRES 2 in the Regulation of Circulating Serum

Chemerin is an adipokine proposed to link obesity and chronic inflammation of adipose tissue. Genetic factors determining chemerin release from adipose tissue are yet unknown. We conducted a meta-analysis of genome-wide association studies (GWAS) for serum chemerin in three independent cohorts from Europe: Sorbs and KORA from Germany and PPP-Botnia from Finland (total N = 2,791). In addition, we measured mRNA expression of genes within the associated loci in peripheral mononuclear cells by micro-arrays, and within adipose tissue by quantitative RT-PCR and performed mRNA expression quantitative trait and expression-chemerin association studies to functionally substantiate our loci. Heritability estimate of circulating chemerin levels was 16.2% in the Sorbs cohort. Thirty single nucleotide polymorphisms (SNPs) at chromosome 7 within the retinoic acid receptor responder 2 (RARRES2)/Leucine Rich Repeat Containing (LRRC61) locus reached genomewide significance (p,5.0610) in the meta-analysis (the strongest evidence for association at rs7806429 with p = 7.8610, beta = 20.067, explained variance 2.0%). All other SNPs within the cluster were in linkage disequilibrium with rs7806429 (minimum r = 0.43 in the Sorbs cohort). The results of the subgroup analyses of males and females were consistent with the results found in the total cohort. No significant SNP-sex interaction was observed. rs7806429 was associated with mRNA expression of RARRES2 in visceral adipose tissue in women (p,0.05 after adjusting for age and body mass index). In conclusion, the present meta-GWAS combined with mRNA expression studies highlights the role of genetic variation in the RARRES2 locus in the regulation of circulating chemerin concentrations. Citation: Tönjes A, Scholz M, Breitfeld J, Marzi C, Grallert H, et al. (2014) Genome Wide Meta-analysis Highlights the Role of Genetic Variation in RARRES2 in the Regulation of Circulating Serum Chemerin. PLoS Genet 10(12): e1004854. doi:10.1371/journal.pgen.1004854 Editor: Eleftheria Zeggini, Wellcome Trust Sanger Institute, United Kingdom Received June 4, 2014; Accepted October 27, 2014; Published December 18, 2014 Copyright: 2014 Tönjes et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability: The authors confirm that all data underlying the findings are fully available without restriction. All relevant data are within the paper and its Supporting Information file. Funding: Sorbs: This work was supported by grants from the German Research Council (SFB-1052 ‘‘Obesity mechanisms’’ B01, B03, B04, C01; SPP 1629 TO 718/21), from the German Diabetes Association and from the DHFD (Diabetes Hilfsund Forschungsfonds Deutschland). IFB Adiposity Diseases is supported by the Federal Ministry of Education and Research (BMBF), Germany, FKZ: 01EO1001. AG, HK and MSc were funded by the Leipzig Interdisciplinary Research Cluster of Genetic Factors, Clinical Phenotypes and Environment (LIFE Center, Universität Leipzig). LIFE is funded by the European Union, by the European Regional Development Fund (ERFD), the European Social Fund and by the Free State of Saxony within the framework of the excellence initiative. KORA: The KORA research platform was initiated and financed by the Helmholtz Center Munich, and by the German Research Center for Environmental Health, which is funded by the German Federal Ministry of Education and Research (BMBF) and by the State of Bavaria. This study was also supported in part by a grant from the BMBF to the German Center for Diabetes Research (DZD). Prevalence, Prediction and Prevention of Diabetes (PPP)-Botnia Study: The PPP–Botnia study in Finland was financially supported by grants from the Sigrid Juselius Foundation, the Folkhälsan Research Foundation, the Signe and Ane Gyllenberg Foundation, the Finnish Diabetes Research Foundation, the Foundation for Life and Health in Finland, the Finnish Medical Society, the Ollqvist Foundation and the Närpes Health Care Foundation. Funding has also been received in Sweden from the Swedish Research Council, including a Linné grant (No. 31475113580), and the Wallenberg Foundation. The DGI GWAS was carried out in collaboration with the Broad Institute and Novartis and funded by a grant from Novartis Pharma. The analyses performed at Lund University were supported by grants from the Swedish Research Council, including a Linnaeus Centre of Excellence grant (Dnr 2006-237) and a project grant (Dnr 2010-3490) to LG. Leipzig cohort: This work was supported by the Kompetenznetz Adipositas (Competence network for Obesity) funded by the Federal Ministry of Education and Research (German Obesity Biomaterial Bank; FKZ 01GI1128), and also by a grant from Deutsche Forschungsgemeinschaft (the PLOS Genetics | www.plosgenetics.org 1 December 2014 | Volume 10 | Issue 12 | e1004854 SFB 1052 ‘‘Obesity mechanisms’’). DS is funded by the Boehringer Ingelheim Foundation. LIFE Heart Study: The LIFE-Heart study was funded by LIFE – Leipzig Research Center for Civilization Diseases, University of Leipzig. LIFE is funded by means of the European Union, by the European Regional Development Fund (ERDF) and by means of the Free State of Saxony within the framework of the excellence initiative. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * Email: michael.stumvoll@medizin.uni-leipzig.de (MSt); peter.kovacs@medizin.uni-leipzig.de (PK) . These authors contributed equally to this work.

[1]  M. Stephens,et al.  High-Resolution Mapping of Expression-QTLs Yields Insight into Human Gene Regulation , 2008, PLoS genetics.

[2]  D. Stephan,et al.  A survey of genetic human cortical gene expression , 2007, Nature Genetics.

[3]  Quin F. Wills,et al.  Coexpression Network Analysis in Abdominal and Gluteal Adipose Tissue Reveals Regulatory Genetic Loci for Metabolic Syndrome and Related Phenotypes , 2012, PLoS genetics.

[4]  Christian Gieger,et al.  Population-genetic comparison of the Sorbian isolate population in Germany with the German KORA population using genome-wide SNP arrays , 2011, BMC Genetics.

[5]  M. Carless,et al.  Chemerin, a novel adipokine in the regulation of angiogenesis. , 2010, The Journal of clinical endocrinology and metabolism.

[6]  R. Turner,et al.  Homeostasis model assessment: insulin resistance and β-cell function from fasting plasma glucose and insulin concentrations in man , 1985, Diabetologia.

[7]  Kerstin Dietrich,et al.  Genetic Variation in Gpr133 Is Associated with Height: Genome Wide Association Study in the Self-contained Population of Sorbs Coordination Centre for Clinical Trials , 2022 .

[8]  Cheng Li,et al.  Adjusting batch effects in microarray expression data using empirical Bayes methods. , 2007, Biostatistics.

[9]  C. Gieger,et al.  KORA-gen - Resource for Population Genetics, Controls and a Broad Spectrum of Disease Phenotypes , 2005, Gesundheitswesen (Bundesverband der Arzte des Offentlichen Gesundheitsdienstes (Germany)).

[10]  D. Koller,et al.  Population genomics of human gene expression , 2007, Nature Genetics.

[11]  Yurii S. Aulchenko,et al.  A Genomic Background Based Method for Association Analysis in Related Individuals , 2007, PloS one.

[12]  Jacob F. Degner,et al.  Sequence and Chromatin Accessibility Data Accurate Inference of Transcription Factor Binding from Dna Material Supplemental Open Access , 2022 .

[13]  John Novembre,et al.  Genetic variation in the Sorbs of eastern Germany in the context of broader European genetic diversity , 2011, European Journal of Human Genetics.

[14]  Z. Zakeri,et al.  Association between chemerin rs17173608 and vaspin rs2236242 gene polymorphisms and the metabolic syndrome, a preliminary report. , 2012, Gene.

[15]  M. Fasshauer,et al.  Circulating Levels of the Adipokine Chemerin in Gestational Diabetes Mellitus , 2010, Hormone Research in Paediatrics.

[16]  D. Reich,et al.  Principal components analysis corrects for stratification in genome-wide association studies , 2006, Nature Genetics.

[17]  J. Blangero,et al.  Chemerin is associated with metabolic syndrome phenotypes in a Mexican-American population. , 2009, The Journal of clinical endocrinology and metabolism.

[18]  M. Stumvoll,et al.  Oral glucose tolerance test indexes for insulin sensitivity and secretion based on various availabilities of sampling times. , 2001, Diabetes care.

[19]  Markus Scholz,et al.  Rationale and Design of the Leipzig (LIFE) Heart Study: Phenotyping and Cardiovascular Characteristics of Patients with Coronary Artery Disease , 2011, PloS one.

[20]  E. Butcher,et al.  Chemerin Activation by Serine Proteases of the Coagulation, Fibrinolytic, and Inflammatory Cascades* , 2005, Journal of Biological Chemistry.

[21]  M. Netea,et al.  Autophagy in adipose tissue and the beta cell: implications for obesity and diabetes , 2014, Diabetologia.

[22]  C. Haley,et al.  Genomewide Rapid Association Using Mixed Model and Regression: A Fast and Simple Method For Genomewide Pedigree-Based Quantitative Trait Loci Association Analysis , 2007, Genetics.

[23]  Richard Startz,et al.  The Distribution of the Instrumental Variables Estimator and its T-Ratiowhen the Instrument is a Poor One , 1988 .

[24]  M. Czaja,et al.  Autophagy regulates adipose mass and differentiation in mice. , 2009, The Journal of clinical investigation.

[25]  F. Collins,et al.  Potential etiologic and functional implications of genome-wide association loci for human diseases and traits , 2009, Proceedings of the National Academy of Sciences.

[26]  Marc Parmentier,et al.  Specific Recruitment of Antigen-presenting Cells by Chemerin, a Novel Processed Ligand from Human Inflammatory Fluids , 2003, The Journal of experimental medicine.

[27]  Marcia M. Nizzari,et al.  Genome-Wide Association Analysis Identifies Loci for Type 2 Diabetes and Triglyceride Levels , 2007, Science.

[28]  P. Zimmet,et al.  Chemerin is a novel adipokine associated with obesity and metabolic syndrome. , 2007, Endocrinology.

[29]  F. Schick,et al.  RARRES2, encoding the novel adipokine chemerin, is a genetic determinant of disproportionate regional body fat distribution: a comparative magnetic resonance imaging study. , 2009, Metabolism: clinical and experimental.

[30]  E. Butcher,et al.  Chemerin, a Novel Adipokine That Regulates Adipogenesis and Adipocyte Metabolism* , 2007, Journal of Biological Chemistry.

[31]  M. Reiser,et al.  Chemerin is associated with markers of inflammation and components of the metabolic syndrome but does not predict coronary atherosclerosis. , 2009, European journal of endocrinology.

[32]  Alexander E. Kel,et al.  TRANSFAC® and its module TRANSCompel®: transcriptional gene regulation in eukaryotes , 2005, Nucleic Acids Res..

[33]  Eurie L. Hong,et al.  Annotation of functional variation in personal genomes using RegulomeDB , 2012, Genome research.

[34]  W. Rathmann,et al.  Genetic variation in the vaspin gene affects circulating serum vaspin concentrations , 2013, International Journal of Obesity.

[35]  M. Komatsu,et al.  Adipose-specific deletion of autophagy-related gene 7 (atg7) in mice reveals a role in adipogenesis , 2009, Proceedings of the National Academy of Sciences.

[36]  L. Groop,et al.  A family history of diabetes is associated with reduced physical fitness in the Prevalence, Prediction and Prevention of Diabetes (PPP)–Botnia study , 2010, Diabetologia.