title: Association between vitamin D receptor gene polymorphisms and severe chronic periodontitis in a Chinese population.
abstract: BACKGROUND
  Chronic periodontitis (CP) exhibits inflammation and alveolar bone loss, and severe forms of periodontitis are suggested to have a genetic basis. Vitamin D receptor (VDR) regulates bone metabolism and inflammation-related genes, and single nucleotide polymorphisms (SNPs) in the VDR gene may affect the functional activity of the VDR protein in CP. Therefore, the aim of this study was to investigate the association between VDR SNPs and severe CP in a Chinese population.
  
  
  METHODS
  DNA was obtained from 107 patients with severe CP and 121 control subjects. The BsmI, TaqI, ApaI, and FokI SNPs of VDR genes were investigated by restriction fragment length polymorphism of polymerase chain reaction (PCR) products. The digested PCR products were electrophoresed on an 8% polyacrylamide gel and developed by the DNA silver staining method.
  
  
  RESULTS
  The distribution of VDR TaqI genotypes and alleles between the two groups was significantly different (P = 0.019 and P = 0.039, respectively). The TT genotype and T allele seemed to increase the susceptibility of severe CP (odds ratio, 2.75; 95% confidence interval [CI]: 1.17 to 6.47; odds ratio, 2.28, 95% CI: 1.02 to 5.06, respectively) in Chinese populations. There was no significant difference in the genotype distribution or the allele frequencies of VDR BsmI, ApaI, or FokI between the two groups.
  
  
  CONCLUSIONS
  TaqI SNP of VDR gene might be associated with severe CP in Chinese patients.
authors.affiliation: Department of Periodontology, Guangdong Provincial Stomatological Hospital, Southern Medical University, Guangzhou, China.
authors.forename: Chunxian
authors.initials: C
authors.lastname: Wang
authors.forename: Hongyu
authors.initials: H
authors.lastname: Zhao
authors.forename: Limin
authors.initials: L
authors.lastname: Xiao
authors.forename: Chengjie
authors.initials: C
authors.lastname: Xie
authors.forename: Weihua
authors.initials: W
authors.lastname: Fan
authors.forename: Shuyu
authors.initials: S
authors.lastname: Sun
authors.forename: Baoyi
authors.initials: B
authors.lastname: Xie
authors.forename: Jincai
authors.initials: J
authors.lastname: Zhang