title: Toll-like receptors 2 and 4 gene polymorphisms in a Chinese population with periodontitis.
abstract: OBJECTIVE
  Polymorphisms for toll-like receptor (TLR) 2 gene (Arg677Trp, Arg753Gln) and TLR4 gene (Asp299Gly, Thr399Ile) that are associated with impaired lipopolysaccharide (LPS) signal transduction have recently been described. The present study aimed to investigate the relationship between TLRs 2 and 4 gene polymorphisms and periodontitis in a Chinese population.
  
  
  METHODS
  Forty patients with generalized aggressive periodontitis, 50 patients with chronic periodontitis, and 100 periodontally healthy controls were recruited. All these subjects were of Han Chinese ethnicity. Genomic DNA was extracted from whole-blood samples. TLRs 2 and 4 genes were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) with respective restriction endonucleases. The alleles were detected by polyacrylamide gel electrophoresis and visualized with ethidium bromide.
  
  
  RESULTS
  Heterozygosity for the TLR2 Arg677Trp polymorphism was found in all subjects. The TLR2 Arg753Gln mutant allele was not found in periodontitis patients, while a heterozygous frequency of 6% (6 of 100) was detected in the controls. The TLR4 Asp299Gly and Thr399Ile mutant alleles were not found in any of the subjects.
  
  
  CONCLUSIONS
  TLR2 Arg753Gln polymorphism may not be associated with aggressive or chronic periodontitis in the Chinese population. The prevalence of TLR2 Arp677Trp polymorphism seemed to be rather high, while that of TLR4 Asp299Gly and Thr399Ile polymorphisms seemed to be rather low in the Chinese population, which did not permit any conclusion regarding its effects on periodontitis.
authors.affiliation: Department of Periodontology, Wuhan University, Wuhan, China.
authors.forename: Guangxun
authors.initials: G
authors.lastname: Zhu
authors.forename: Chengzhang
authors.initials: C
authors.lastname: Li
authors.forename: Zhengguo
authors.initials: Z
authors.lastname: Cao
authors.forename: Esmonde F
authors.initials: EF
authors.lastname: Corbet
authors.forename: Lijian
authors.initials: L
authors.lastname: Jin
mesh_terms: D000483:Alleles; D016022:Case-Control Studies; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D010518:Periodontitis / Q000235:genetics*; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide; D051195:Toll-Like Receptor 2 / Q000235:genetics*; D051197:Toll-Like Receptor 4 / Q000235:genetics*
chemical_list: D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4