title: A functional EGF+61 polymorphism is associated with severity of obstructive sleep apnea.
abstract: BACKGROUND
  Involvement of epidermal growth factor (EGF) is reported in diseases caused by hypoxia. Its functional polymorphism may alter its transcription, affecting EGF expression, contributing to obstructive sleep apnea (OSA).
  
  
  OBJECTIVE
  The aim of this study was to investigate associations of EGF+61 polymorphism and risk of OSA.
  
  
  METHODS
  Two hundred two participants were enrolled in this case-control study. DNA was extracted from peripheral blood, and EGF 61A/G polymorphism was determined using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay.
  
  
  RESULTS
  No significant association between EGF 61 A/G polymorphism and risk of OSA was observed in any of the gene models tested (AA vs. GG: OR = 0.97, 95% CI = 0.37-2.55; P = 0.95). However, compared with GG genotype, AG genotype associated with decreased risk of severe OSA (AG vs. GG: OR = 0.32, 95% CI = 0.11-0.94).
  
  
  CONCLUSIONS
  Our study showed that AG genotype has a protective effect on OSA patients against severe disease, although EGF 61A/G polymorphisms have no role on the risk of the disease. Additional large studies should further validate our findings.
authors.affiliation: Department of Respiratory Medicine, Affiliated Hospital of School of Medicine, Ningbo University, Ningbo, 315020, China.
authors.forename: Qunli
authors.initials: Q
authors.lastname: Ding
authors.forename: Chao
authors.initials: C
authors.lastname: Cao
authors.forename: Zhongbo
authors.initials: Z
authors.lastname: Chen
authors.forename: Mahebali
authors.initials: M
authors.lastname: Tabusi
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Zaichun
authors.initials: Z
authors.lastname: Deng
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D004815:Epidermal Growth Factor / Q000235:genetics*; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics; D005799:Genes, Dominant; D006580:Genetic Carrier Screening; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005838:Genotype; D006720:Homozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D008957:Models, Genetic; D011110:Polymorphism, Genetic / Q000235:genetics*; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics
chemical_list: D004815:Epidermal Growth Factor