title: Strong association between the -308 TNF promoter polymorphism and allergic rhinitis in Pakistani patients.
abstract: BACKGROUND
  Allergic rhinitis (AR) is a common complex allergic inflammatory disorder. The tumor necrosis factor (TNF) alpha polymorphism G-308A is present in the promoter region of the gene and considered to be important due to its role in different allergic diseases.
  
  
  OBJECTIVE
  We aimed to identify genetic associations between this polymorphism and AR in patients of Pakistani origin.
  
  
  METHODS
  We analyzed the distribution of G-308A in 153 unrelated AR patients and 116 unrelated healthy controls. Samples were genotyped for G-308A using restriction fragment length polymorphism.
  
  
  RESULTS
  The TNF -308A allele (TNF2) was significantly more frequent in patients with AR (37%) than in controls (16%, P<.001; chi2=32.15). Genotype distribution was also significantly different between patients and controls (P<.001; chi2=40.81). The TNF2 homozygous genotype and TNF1/2 heterozygous genotype were significantly more common in AR patients (TNF2, 12%; TNF1/2, 49%) than in controls (TNF2, 4%; TNF1/2, 23%), whereas the normal TNF1 homozygous genotype was more frequent in controls (73%) than in patients (39%).
  
  
  CONCLUSIONS
  Our results suggest a strong association between the promoter polymorphism of TNF-alpha and AR in Pakistani cohorts.
authors.affiliation: Department of Biosciences, COMSATS Institute of Information Technology, Islamabad, Pakistan.
authors.forename: K
authors.initials: K
authors.lastname: Minhas
authors.forename: S
authors.initials: S
authors.lastname: Micheal
authors.forename: F
authors.initials: F
authors.lastname: Ahmed
authors.forename: A
authors.initials: A
authors.lastname: Ahmed
mesh_terms: D000328:Adult; D000483:Alleles; D016009:Chi-Square Distribution; D015331:Cohort Studies; D004247:DNA / Q000737:chemistry / Q000235:genetics; D005260:Female; D014644:Genetic Variation; D006801:Humans; D008297:Male; D010154:Pakistan; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D012221:Rhinitis, Allergic, Perennial / Q000235:genetics*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*
chemical_list: D014409:Tumor Necrosis Factor-alpha; D004247:DNA