title: Interferon gamma gene polymorphism as a biochemical marker in Egyptian atopic patients.
abstract: OBJECTIVE
  The aim of this study was to clarify the role of interferon (IFN) gamma in the diagnosis and follow-up of atopic patients. We genotyped the IFN-gamma polymorphism at position +874 to examine the relationship between serum levels of IFN-gamma and disease severity and the role of IFN-gamma as a biochemical and immunologic marker.
  
  
  METHODS
  The study population comprised 75 patients suffering from atopic asthma, atopic dermatitis, and allergic rhinitis (25 each), and 25 control participants. Total immunoglobulin (Ig) E and serum IFN-gamma were measured by enzyme-linked immunosorbent assay, the IFN-gamma polymorphism at position +874 was determined by amplification refractory mutation system-polymerase chain reaction, and eosinophil counts were recorded.
  
  
  RESULTS
  There was a significant association between genotype and the frequency of the A allele of the +874T/A polymorphism in atopic patients when compared with controls (P < .001). In all 3 groups, there was a significant increase in total IgE levels and eosinophil counts, and a decrease in serum IFN-gamma levels towards the presence of homozygous AA compared with homozygous TT.
  
  
  CONCLUSIONS
  The IFN-gamma gene polymorphism at position +874 contributes to susceptibility to atopic diseases by decreasing the amount of IFN-gamma. Identification of variants of IFN-gamma gene signalling and its role in the development of atopic diseases provides a focus for the development of novel diagnostic and therapeutic strategies for these diseases.
authors.affiliation: Medical Biochemistry Department, Faculty of Medicine, Zagazig University, Egypt. yousrihussein@hotmail.com
authors.forename: Y M
authors.initials: YM
authors.lastname: Hussein
authors.forename: A S
authors.initials: AS
authors.lastname: Ahmad
authors.forename: M M
authors.initials: MM
authors.lastname: Ibrahem
authors.forename: S A
authors.initials: SA
authors.lastname: El Tarhouny
authors.forename: S M
authors.initials: SM
authors.lastname: Shalaby
authors.forename: A S
authors.initials: AS
authors.lastname: Elshal
authors.forename: M
authors.initials: M
authors.lastname: El Said
mesh_terms: D015415:Biomarkers / Q000097:blood; D002452:Cell Count; D018450:Disease Progression; D004534:Egypt; D004804:Eosinophils / Q000473:pathology; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000097:blood / Q000175:diagnosis / Q000235:genetics* / Q000276:immunology* / Q000503:physiopathology; D007073:Immunoglobulin E / Q000097:blood; D007371:Interferon-gamma / Q000097:blood / Q000235:genetics* / Q000276:immunology*; D011110:Polymorphism, Genetic; D011379:Prognosis; D012882:Skin Tests
chemical_list: D015415:Biomarkers; D007073:Immunoglobulin E; D007371:Interferon-gamma