title: Genetic Polymorphisms of Toll-like Receptor 4 are Associated with Respiratory Syncytial Virus Infection in a Chinese Infant Population.
abstract: BACKGROUND
  While genetic polymorphisms in Toll-like Receptor 4 (TLR4) have been demonstrated to play an important role in respiratory syncytial virus (RSV) infections in Western populations, the association between TLR4 polymorphisms and RSV infections has not been investigated in Chinese patient populations. The study presented here identifies TLR4 polymorphisms and investigates the association of TLR4 genetic polymorphism with RSV infection in a Chinese infant patient population.
  
  
  METHODS
  One-hundred and ninety-six infants hospitalized with RSV infections and 311 healthy control subjects were enrolled in this study. Genetic polymorphisms in the 5' untranslated region (5'UTR), exons, and 3' untranslated region (3'UTR) of the TLR4 gene were screened using PCR and sequencing analysis. The association between the genetic polymorphisms in TLR4, RSV infection risk, and the related disease severity was investigated using Fisher's Exact Test and the Chi-square test.
  
  
  RESULTS
  Fourteen different genetic polymorphisms within the TLR4 gene, including two in the 5'UTR, four in the exons, and eight in the 3'UTR were found in the study population. Two polymorphisms, Asp299Gly and Thr399Ile, typically associated with RSV in Caucasian infants were not observed in the Chinese infants. Of the 14 polymorphisms, only rs41426344 (G/C) in the 3'UTR of the TLR4 gene was found to be associated with RSV infection risk and disease severity.
  
  
  CONCLUSIONS
  The TLR4 genetic polymorphism rs41426344 may be a specific genetic risk factor in Chinese infants associated with RSV infection and disease severity.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhu
authors.forename: Zhou
authors.initials: Z
authors.lastname: Fu
authors.forename: Li
authors.initials: L
authors.lastname: Gao
authors.forename: Lijia
authors.initials: L
authors.lastname: Wang
authors.forename: Enmei
authors.initials: E
authors.lastname: Liu
authors.forename: Daiyin
authors.initials: D
authors.lastname: Tian
mesh_terms: D020413:3' Untranslated Regions; D020121:5' Untranslated Regions; D044466:Asian People; D002648:Child; D002675:Child, Preschool; D002681:China; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006760:Hospitalization; D006801:Humans; D007223:Infant; D008297:Male; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D018357:Respiratory Syncytial Virus Infections / Q000208:ethnology / Q000235:genetics*; D012136:Respiratory Syncytial Viruses; D012307:Risk Factors; D051197:Toll-Like Receptor 4 / Q000235:genetics*
chemical_list: D020413:3' Untranslated Regions; D020121:5' Untranslated Regions; C495345:TLR4 protein, human; D051197:Toll-Like Receptor 4