title: TNFA -308G>A in two international population-based cohorts and risk of asthma.
abstract: Genetic association studies have related the tumour necrosis factor-alpha gene (TNFA) guanine to adenine substitution of nucleotide -308 (-308G>A) polymorphism to increased risk of asthma, but results are inconsistent. The aim of the present study was to test whether two single-nucleotide polymorphisms, of TNFA and of the lymphotoxin-alpha gene (LTA), are associated with asthma, bronchial hyperresponsiveness and atopy in adults, by combining the results of two large population-based multicentric studies and conducting a meta-analysis of previously published studies. The European Community Respiratory Health Survey (ECRHS) and Swiss Cohort Study on Air Pollution and Lung and Heart Diseases in Adults (SAPALDIA) used comparable protocols, including questionnaires for respiratory symptoms and measures of lung function and atopy. DNA samples from 11,136 participants were genotyped at TNFA -308 and LTA 252. Logistic regression employing fixed and random effects models and nonparametric techniques were used. The prevalence of asthma was 6%. The TNFA -308G>A polymorphism was associated with increased asthma prevalence and with bronchial hyperresponsiveness. No consistent association was found for atopy. The LTA 252A>G polymorphism was not associated with any of the outcomes. A meta-analysis of 17 studies showed an increased asthma risk for the TNFA -308 adenine allele. The tumour necrosis factor-alpha gene nucleotide -308 polymorphism is associated with a moderately increased risk of asthma and bronchial hyperresponsiveness, but not with atopy. These results are supported by a meta-analysis of previously published studies.
authors.affiliation: Centre de Recerca en Epidemiologia Ambiental (CREAL), Barcelona, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Castro-Giner
authors.forename: M
authors.initials: M
authors.lastname: Kogevinas
authors.forename: M
authors.initials: M
authors.lastname: Mächler
authors.forename: R
authors.initials: R
authors.lastname: de Cid
authors.forename: K
authors.initials: K
authors.lastname: Van Steen
authors.forename: M
authors.initials: M
authors.lastname: Imboden
authors.forename: C
authors.initials: C
authors.lastname: Schindler
authors.forename: W
authors.initials: W
authors.lastname: Berger
authors.forename: J R
authors.initials: JR
authors.lastname: Gonzalez
authors.forename: K A
authors.initials: KA
authors.lastname: Franklin
authors.forename: C
authors.initials: C
authors.lastname: Janson
authors.forename: D
authors.initials: D
authors.lastname: Jarvis
authors.forename: E
authors.initials: E
authors.lastname: Omenaas
authors.forename: P
authors.initials: P
authors.lastname: Burney
authors.forename: T
authors.initials: T
authors.lastname: Rochat
authors.forename: X
authors.initials: X
authors.lastname: Estivill
authors.forename: J M
authors.initials: JM
authors.lastname: Antó
authors.forename: M
authors.initials: M
authors.lastname: Wjst
authors.forename: N M
authors.initials: NM
authors.lastname: Probst-Hensch
mesh_terms: D000293:Adolescent; D000328:Adult; D000483:Alleles; D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics* / Q000473:pathology; D001980:Bronchi / Q000378:metabolism / Q000473:pathology; D016535:Bronchial Hyperreactivity / Q000175:diagnosis / Q000235:genetics*; D015331:Cohort Studies; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D012306:Risk; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics* / Q000502:physiology
chemical_list: D014409:Tumor Necrosis Factor-alpha