Polymorphisms related to ORMDL3 are associated with asthma susceptibility, alterations in transcriptional regulation of ORMDL3, and changes in TH2 cytokine levels.
BACKGROUND
Chromosome 17q21, harboring the orosomucoid 1-like 3 (ORMDL3) gene, has been consistently associated with childhood asthma in genome-wide association studies.


OBJECTIVE
We investigated genetic variants in and around ORMDL3 that can change the function of ORMDL3 and thus contribute to asthma susceptibility.


METHODS
We performed haplotype analyses and fine mapping of the ORMDL3 locus in a cross-sectional (International Study of Asthma and Allergies in Childhood Phase II, n = 3557 total subjects, n = 281 asthmatic patients) and case-control (Multicenter Asthma Genetics in Childhood Study/International Study of Asthma and Allergies in Childhood Phase II, n = 1446 total subjects, n = 763 asthmatic patients) data set to identify putative causal single nucleotide polymorphisms (SNPs) in the locus. Top asthma-associated polymorphisms were analyzed for allele-specific effects on transcription factor binding and promoter activity in vitro and gene expression in PBMCs after stimulation ex vivo.


RESULTS
Two haplotypes (H1 and H2) were significantly associated with asthma in the cross-sectional (P = 9.9 × 10(-5) and P = .0035, respectively) and case-control (P = 3.15 × 10(-8) and P = .0021, respectively) populations. Polymorphisms rs8076131 and rs4065275 were identified to drive these effects. For rs4065275, a quantitative difference in transcription factor binding was found, whereas for rs8076131, changes in upstream stimulatory factor 1 and 2 transcription factor binding were observed in vitro by using different cell lines and PBMCs. This might contribute to detected alterations in luciferase activity paralleled with changes in ORMDL3 gene expression and IL-4 and IL-13 cytokine levels ex vivo in response to innate and adaptive stimuli in an allele-specific manner. Both SNPs were in strong linkage disequilibrium with asthma-associated 17q21 SNPs previously related to altered ORMDL3 gene expression.


CONCLUSIONS
Polymorphisms in a putative promoter region of ORMDL3, which are associated with childhood asthma, alter transcriptional regulation of ORMDL3, correlate with changes in TH2 cytokines levels, and therefore might contribute to the childhood asthma susceptibility signal from 17q21.
Department of Pediatrics, National Jewish Health, Denver, Colo; Department of Pediatric Pneumology, Allergy, and Neonatology, Hannover Medical School, Hannover, Germany.
Michaela
M
Schedel
Department of Pediatric Pneumology and Allergy, University Children's Hospital Regensburg (KUNO), Regensburg, Germany; Department of Pediatric Pneumology, Allergy, and Neonatology, Hannover Medical School, Hannover, Germany.
Sven
S
Michel
Department of Pediatric Pneumology and Allergy, University Children's Hospital Regensburg (KUNO), Regensburg, Germany.
Vincent D
VD
Gaertner
Department of Pediatric Pneumology and Allergy, University Children's Hospital Regensburg (KUNO), Regensburg, Germany; Department of Pediatric Pneumology, Allergy, and Neonatology, Hannover Medical School, Hannover, Germany.
Antoaneta A
AA
Toncheva
Children's Hospital, Ludwig-Maximilians-Universität, Munich, Germany.
Martin
M
Depner
Department of Pediatric Pneumology and Allergy, University Children's Hospital Regensburg (KUNO), Regensburg, Germany; Nestlé Research Centre, Nutrition & Health Department, Lausanne, Switzerland.
Aristea
A
Binia
Department of Pediatric Pneumology and Allergy, University Children's Hospital Regensburg (KUNO), Regensburg, Germany; Department of Pediatric Pneumology, Allergy, and Neonatology, Hannover Medical School, Hannover, Germany.
Maximilian
M
Schieck
Children's Hospital, Ludwig-Maximilians-Universität, Munich, Germany.
Marie T
MT
Rieger
Research Group of Molecular Epidemiology, Helmholtz Centre Munich, Neuherberg, Germany; Hannover Unified Biobank, Hannover Medical School, Hannover, Germany.
Norman
N
Klopp
Research Institute for the Prevention of Allergic Diseases, Children's Department, Marien-Hospital, Wesel, Germany.
Andrea
A
von Berg
Department of Experimental Pneumology, Ruhr-University, Bochum, Germany.
Albrecht
A
Bufe
Children's Hospital, Ludwig-Maximilians-Universität, Munich, Germany.
Otto
O
Laub
University Children's Hospital, University of Cologne, Cologne, Germany.
Ernst
E
Rietschel
University Children's Hospital, Albert Ludwigs University, Freiburg, Germany.
Andrea
A
Heinzmann
Children's Department, Feldkirch Hospital, Feldkirch, Austria.
Burkard
B
Simma
University Children's Hospital, Technical University Dresden, Germany.
Christian
C
Vogelberg
Institute of Epidemiology and Medical Biometry, Ulm University, Ulm, Germany.
Jon
J
Genuneit
Research Group of Molecular Epidemiology, Helmholtz Centre Munich, Neuherberg, Germany; Hannover Unified Biobank, Hannover Medical School, Hannover, Germany.
Thomas
T
Illig
Department of Pediatric Pneumology and Allergy, University Children's Hospital Regensburg (KUNO), Regensburg, Germany; Department of Pediatric Pneumology, Allergy, and Neonatology, Hannover Medical School, Hannover, Germany. Electronic address: michael.kabesch@ukr.de.
Michael
M
Kabesch
D001249:Asthma / Q000235:genetics* / Q000276:immunology*; D016022:Case-Control Studies; D002478:Cells, Cultured; D002648:Child; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics*; D003430:Cross-Sectional Studies; D004252:DNA Mutational Analysis; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005858:Germany; D006239:Haplotypes; D006801:Humans; D018793:Interleukin-13 / Q000378:metabolism; D015847:Interleukin-4 / Q000378:metabolism; D007391:International Cooperation; D007963:Leukocytes, Mononuclear / Q000502:physiology*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic / Q000235:genetics; D058408:Th1-Th2 Balance; D018418:Th2 Cells / Q000276:immunology*
D018793:Interleukin-13; D008565:Membrane Proteins; C464399:ORMDL3 protein, human; D015847:Interleukin-4
Asthma; ORMDL3; T(H)2 cytokine; association study; chromosome 17q21; polymorphism; promoter activity; transcriptional regulation; upstream stimulatory factor