title: Carriers of aVEGFAenhancer polymorphism selectively binding CHOP/DDIT3 are predisposed to increased circulating levels of thyroid-stimulating hormone.
abstract: Levels of serum thyroid-stimulating hormone (TSH) indicate thyroid function, because thyroid hormone negatively controls TSH release. Genetic variants in the vascular endothelial growth factor A (VEGFA) gene are associated with TSH levels. The aim of this study was to characterise the association ofVEGFAvariants with TSH in a Danish cohort and to identify and characterise functional variants.
  
  
  
  We performed an association study of theVEGFAlocus for circulating TSH levels in 8445 Danish individuals. Lead variants were tested for allele-specific effects in vitro using luciferase reporter and gel-shift assays.
  
  
  
  Four SNPs inVEGFAwere associated with circulating TSH (rs9472138, rs881858, rs943080 and rs4711751). For rs881858, the presence of each G-allele was associated with a corresponding decrease in TSH levels of 2.3% (p=8.4×10-9) and an increase in circulating free T4 levels (p=0.0014). The SNP rs881858 is located in a binding site for CHOP (C/EBP homology protein) and c/EBPβ (ccaat enhancer binding protein β). Reporter-gene analysis showed increased basal enhancer activity of the rs881858 A-allele versus the G-allele (34.5±9.9% (average±SEM), p=0.0012), while co-expression of CHOP effectively suppressed the rs881858 A-allele activity. The A-allele showed stronger binding to CHOP in gel-shift assays.
  
  
  
  VEGF is an important angiogenic signal required for tissue expansion. We show thatVEGFAvariation giving allele-specific response to transcription factors with overlapping binding sites associate closely with circulating TSH levels. Because CHOP is induced by several types of intracellular stress, this indicates that cellular stress could be involved in the normal or pathophysiological response of the thyroid to TSH.
  
  
  
  NCT00289237, NCT00316667; Results.
authors.affiliation: The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.|Steno Diabetes Center, Gentofte, Denmark.
authors.forename: Tarunveer Singh
authors.initials: TS
authors.lastname: Ahluwalia
authors.affiliation: Department of Science and Environment, Roskilde University, Roskilde, Denmark.
authors.forename: Jesper Thorvald
authors.identifier: 0000-0002-4177-3267
authors.initials: JT
authors.lastname: Troelsen
authors.affiliation: The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Marie
authors.initials: M
authors.lastname: Balslev-Harder
authors.affiliation: The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Jette
authors.initials: J
authors.lastname: Bork-Jensen
authors.affiliation: Research Centre for Prevention and Health, The Capital Region, Glostrup, Denmark.
authors.forename: Betina Heinsbæk
authors.initials: BH
authors.lastname: Thuesen
authors.affiliation: Research Centre for Prevention and Health, The Capital Region, Glostrup, Denmark.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Cerqueira
authors.affiliation: Research Centre for Prevention and Health, The Capital Region, Glostrup, Denmark.|Department of Clinical Experimental Research, Rigshospitalet, Copenhagen, Denmark.|Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Allan
authors.initials: A
authors.lastname: Linneberg
authors.affiliation: The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Niels
authors.initials: N
authors.lastname: Grarup
authors.affiliation: The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Oluf
authors.initials: O
authors.lastname: Pedersen
authors.affiliation: The Novo Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.|Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark.
authors.forename: Torben
authors.initials: T
authors.lastname: Hansen
authors.affiliation: Department of Science and Environment, Roskilde University, Roskilde, Denmark.
authors.forename: Louise Torp
authors.identifier: 0000-0002-3598-2775
authors.initials: LT
authors.lastname: Dalgaard
mesh_terms: D003718:Denmark; D004742:Enhancer Elements, Genetic; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006579:Heterozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000097:blood / Q000235:genetics* / Q000473:pathology; D020641:Polymorphism, Single Nucleotide; D011485:Protein Binding / Q000235:genetics; D013961:Thyroid Gland / Q000378:metabolism / Q000473:pathology; D013972:Thyrotropin / Q000097:blood* / Q000172:deficiency / Q000235:genetics; D051742:Transcription Factor CHOP / Q000235:genetics*; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics*
chemical_list: C497249:DDIT3 protein, human; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D051742:Transcription Factor CHOP; D013972:Thyrotropin
keywords: Metabolic disorders; Molecular genetics; insulin resistance; thyroíd; transcription factor