title: IFN-γ CA microsatellite polymorphism is associated with susceptibility to respiratory syncytial virus Infection and severity.
abstract: OBJECTIVE
  IFN-γ, an essential cytokine in the viral cell-mediated immune response, has been associated with the pathogenesis of respiratory syncytial virus (RSV) bronchiolitis and to the severity of the infection. The aim of this study was to investigate whether IFN-γ CA microsatellite (rs3138557) polymorphism was associated with susceptibility to RSV in Chinese Han children and with the severity of the infection.
  
  
  METHODS
  The IFN-γ CA microsatellite was tested in 218 RSV bronchiolitis inpatients and 303 healthy controls, and the severity of the RSV bronchiolitis was evaluated using a standardised respiratory scoring system.
  
  
  RESULTS
  The frequencies of CA12+/CA12+, CA12+/CA12- and CA12-/CA12- in the 218 RSV bronchiolitis patients and 303 controls were approximately 11% versus 19%, 55% versus 53% and 34% versus 28%, respectively. The gene polymorphism of IFN-γ CA repeats between the two groups was statistically different. The clinical respiratory scores of RSV bronchiolitis cases with CA12+/CA12+ and CA12+/CA12- were 2.84 ± 0.40 (SD) and 2.95 ± 0.44 (SD), respectively, and these were significantly lower than the 3.1 ± 0.36 (SD) score for those with CA12-/CA12-.
  
  
  CONCLUSIONS
  IFN-γ CA microsatellite polymorphism was associated with the susceptibility of Chinese Han children to RSV and the severity of the infection.
authors.affiliation: Pulmonology Department, Children's Hospital of Fudan University, Shanghai, China.
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Huang
authors.forename: Mingzhi
authors.initials: M
authors.lastname: Zhang
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Zhang
authors.forename: Aizhen
authors.initials: A
authors.lastname: Lu
authors.forename: Libo
authors.initials: L
authors.lastname: Wang
authors.forename: Chao
authors.initials: C
authors.lastname: Chen
mesh_terms: D001990:Bronchiolitis, Viral / Q000175:diagnosis / Q000235:genetics* / Q000821:virology; D016022:Case-Control Studies; D002681:China; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D007223:Infant; D007371:Interferon-gamma / Q000235:genetics*; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D018357:Respiratory Syncytial Virus Infections / Q000175:diagnosis / Q000235:genetics*; D018113:Respiratory Syncytial Virus, Human; D012720:Severity of Illness Index
chemical_list: D007371:Interferon-gamma
keywords: CA microsatellite; Gene polymorphism; IFN-γ; RSV bronchiolitis