title: Identification of functional tag single nucleotide polmorphisms within the entire CAT gene and their clinical relevance in patients with noise-induced hearing loss.
abstract: OBJECTIVE
  Noise-induced hearing loss (NIHL) is an important occupational disease which results from an interaction between genetic and environmental factors. More and more evidences suggested that Catalase (CAT) gene polymorphism plays an important role in the development of NIHL. The aim of this study was to investigate the association of CAT gene polymorphisms with NIHL in a case-control study.
  
  
  METHODS
  A total of 719 unrelated adult Chinese Han population, including 225 healthy volunteers and 494 noise-exposed workers were recruited in this study. Six tag single-nucleotide polymorphisms (tSNPs) were genotyped using an improved multiplex ligation detection reaction technique. Subsequently, the interaction between noise exposure level and genotypes and their effect on NIHL were analyzed using logistic regression.
  
  
  RESULTS
  Among six tSNPs, two of them (rs208679 and rs769217) were significantly associated with noise exposure level. For rs208679 recessive effect, GG genotype had a significantly increased of NIHL risk in the exposure level of <85 dB; and for rs769217 dominant effect, the combined genotypes TT/TC had a significantly increased of NIHL risk in the exposure level of 85 dB~92 dB; and the haplotype A-G-T-C-A-C had a risk effect on the NIHL in the exposure level of 85 dB~92 dB. In addition, the rs769217 polymorphism could enhance the transcription activities of the CAT gene.
  
  
  CONCLUSIONS
  This study identified CAT is a NIHL susceptibility gene when noise exposure levels are taken into account. Rs208679 and rs769217 polymorphisms might be used as relevant risk estimates for the development of NIHL in population with different noise exposure levels.
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, Daping Hospital, Third Military Medical University Chongqing 400042, China.
authors.forename: Junhui
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department 6 of Research Institute of Surgery, Daping Hospital, Third Military Medical University, State Key Laboratory of Trauma, Burns and Combined Injury Chongqing 400042, China.
authors.forename: Jieyuan
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Prevention and Control Center of Disease of Chongqing Fuling Chongqing 408000, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Wang
authors.affiliation: Chongqing Fuling Central Hospital Chongqing 408000, China.
authors.forename: Chaoyong
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, Daping Hospital, Third Military Medical University Chongqing 400042, China.
authors.forename: Jichuan
authors.initials: J
authors.lastname: Chen
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, Daping Hospital, Third Military Medical University Chongqing 400042, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Qian
authors.affiliation: Department 6 of Research Institute of Surgery, Daping Hospital, Third Military Medical University, State Key Laboratory of Trauma, Burns and Combined Injury Chongqing 400042, China.
authors.forename: Zhaoxia
authors.initials: Z
authors.lastname: Duan
mesh_terms: D000293:Adolescent; D000328:Adult; D044466:Asian People / Q000235:genetics; D001301:Audiometry, Pure-Tone; D016022:Case-Control Studies; D002374:Catalase / Q000235:genetics*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006317:Hearing Loss, Noise-Induced / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D055815:Young Adult
chemical_list: C577219:CAT protein, human; D002374:Catalase
keywords: Noise-induced hearing loss; catalase; clinical relevance; single-nucleotide polymorphism; tag