title: Association between variations in CAT and noise-induced hearing loss in two independent noise-exposed populations.
abstract: Noise-induced hearing loss (NIHL) is an important occupational hazard that results from an interaction between genetic and environmental factors. Although the environmental risk factors have been studied quite extensively, little is known about the genetic factors. On the basis of multiple studies, it was proposed that oxidative stress plays an important role in the development of NIHL. Here, we investigated whether variations (single nucleotide polymorphisms; SNPs) in the catalase gene (CAT), one of the genes involved in oxidative stress, influence noise susceptibility. Audiometric data from 1261 Swedish and 4500 Polish noise-exposed labourers were analysed. DNA samples were collected from the 10% most susceptible and the 10% most resistant individuals. Twelve SNPs were selected and genotyped. Subsequently, the interaction between noise exposure and genotypes and their effect on NIHL were analysed using logistic regression. Significant interactions were observed between noise exposure levels and genotypes of two SNPs for the Swedish population and of five SNPs for the Polish population. Two of these SNPs were significant in both populations. The interaction between predictor haplotypes and tagSNP haplotypes and noise exposure levels and their effect on NIHL were also analysed, resulting in several significant associations. In conclusion, this study identified significant associations between catalase SNPs and haplotypes and susceptibility to development of NIHL. These results indicate that catalase is a NIHL susceptibility gene, but that the effect of CAT polymorphisms can only be detected when noise exposure levels are taken into account.
authors.affiliation: Department of Medical Genetics, University of Antwerp, B-2610 Antwerp, Belgium.
authors.forename: Annelies
authors.initials: A
authors.lastname: Konings
authors.forename: Lut
authors.initials: L
authors.lastname: Van Laer
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Pawelczyk
authors.forename: Per-Inge
authors.initials: PI
authors.lastname: Carlsson
authors.forename: Marie-Louise
authors.initials: ML
authors.lastname: Bondeson
authors.forename: Elzbieta
authors.initials: E
authors.lastname: Rajkowska
authors.forename: Adam
authors.initials: A
authors.lastname: Dudarewicz
authors.forename: Ann
authors.initials: A
authors.lastname: Vandevelde
authors.forename: Erik
authors.initials: E
authors.lastname: Fransen
authors.forename: Jeroen
authors.initials: J
authors.lastname: Huyghe
authors.forename: Erik
authors.initials: E
authors.lastname: Borg
authors.forename: Mariola
authors.initials: M
authors.lastname: Sliwinska-Kowalska
authors.forename: Guy
authors.initials: G
authors.lastname: Van Camp
mesh_terms: D000328:Adult; D002374:Catalase / Q000235:genetics*; D007758:Ear, Inner / Q000378:metabolism; D020022:Genetic Predisposition to Disease; D005828:Genetics, Population; D005838:Genotype; D006239:Haplotypes; D006317:Hearing Loss, Noise-Induced / Q000209:etiology / Q000235:genetics*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure; D018384:Oxidative Stress / Q000235:genetics; D020641:Polymorphism, Single Nucleotide
chemical_list: D002374:Catalase