title: Functional Fcgamma receptor polymorphisms are associated with human allergy.
abstract: OBJECTIVE
  IgG Fc receptors (FcγRs) play important roles in immune responses. It is not clear whether FcγR receptors play a role in human asthma and allergy. The aim of current study was to investigate whether functional single nucleotide polymorphisms (SNPs) of FcγR genes (FCGR) are associated with human asthma and allergy.
  
  
  METHODS
  Functional SNPs of FCGR2A (FcγRIIA-131His>Arg, rs1801274), FCGR2B (FcγRIIB-187Ile>Thr, rs1050501), FCGR2C (FcγRIIC-13Gln>Stop, rs10917661), FCGR3A (FcγRIIIA-158Val>Phe, rs396991), and FCGR3B variants (FcγRIIIB NA1 and NA2) were genotyped in an asthma family cohort including 370 atopy positive, 239 atopy negative, and 169 asthma positive subjects. The genotype and phenotype data (asthma, bronchial hyper-responsiveness, and atopy) of subjects were analyzed using family-based association tests (FBAT) and logistic regression adjusted for age and sex.
  
  
  RESULTS
  The FcγRIIA-131His>Arg SNP is significantly associated with atopy in a family-based association test (P = 0.00287) and in a logistic regression analysis (P = 0.0269, OR 0.732, 95% CI: 0.555-0.965). The FcγRIIA-131His (or rs1801274-A) allele capable of binding human IgG2 has a protective role against atopy. In addition, the rare FcγRIIB-187Thr (or rs1050501-C) allele defective for the receptor-mediated inhibitory signals is a risk factor for atopy (P = 0.0031, OR 1.758, 95% CI: 1.209-2.556) and IgE production (P<0.001). However, variants of activating FcγRIIIA (rs396991), and FcγRIIIB (NA1 and NA2), and FcγRIIC (rs10917661) are not associated with asthma, BHR, and atopy (P>0.05).
  
  
  CONCLUSIONS
  FcγRIIA and FcγRIIB functional polymorphisms may have a role in the pathogenesis of allergy.
authors.affiliation: Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, Minnesota, United States of America ; Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America.
authors.forename: Jianming
authors.initials: J
authors.lastname: Wu
authors.affiliation: Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, Minnesota, United States of America.
authors.forename: Rui
authors.initials: R
authors.lastname: Lin
authors.affiliation: Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, Minnesota, United States of America.
authors.forename: Jinhai
authors.initials: J
authors.lastname: Huang
authors.affiliation: Department of Biostatistics, University of Minnesota, Minneapolis, Minnesota, United States of America.
authors.forename: Weihua
authors.initials: W
authors.lastname: Guan
authors.affiliation: Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minnesota, United States of America.
authors.forename: William S
authors.initials: WS
authors.lastname: Oetting
authors.affiliation: Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, Minnesota, United States of America ; Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America.
authors.forename: P
authors.initials: P
authors.lastname: Sriramarao
authors.affiliation: Department of Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America.
authors.forename: Malcolm N
authors.initials: MN
authors.lastname: Blumenthal
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D001249:Asthma / Q000235:genetics*; D002648:Child; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D006967:Hypersensitivity / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D017452:Receptors, IgG / Q000235:genetics*; D012307:Risk Factors; D055815:Young Adult
chemical_list: D017452:Receptors, IgG