title: The Fcgamma receptor genotype as a risk factor for generalized early-onset periodontitis in Japanese patients.
abstract: BACKGROUND
  Genetic polymorphisms of immunoglobulin G (IgG) Fc receptors (FcgammaR) were recently shown to be associated with recurrence rates of adult periodontitis (AP). The purpose of this study was to evaluate whether FcgammaR polymorphisms are also associated with generalized early-onset periodontitis (G-EOP) in Japanese patients.
  
  
  METHODS
  Thirty-eight Japanese patients with G-EOP and 83 Japanese patients with AP were identified according to established clinical criteria, including measurements of probing depth, clinical attachment level, and alveolar bone level. FcgammaR genotypes for 3 bi-allelic polymorphisms were determined in these G-EOP and AP patients and 104 race-matched healthy controls by means of allele-specific polymerase chain reactions.
  
  
  RESULTS
  There was a significant difference in the distribution of FcgammaRIIIb genotypes between G-EOP patients and healthy controls (P = 0.02). Additionally, a significant over-representation of FcgammaRIIIb-NA2 allele was observed in G-EOP patients as compared to AP patients and controls (P= 0.02, P= 0.009, respectively). Moreover, we found a strong association between G-EOP and the composite genotype comprising FcgammaRIIIb-NA2 and FcgammaRIIIa-158F (G-EOP versus controls: odds ratio 2.4, 95% CI 1.0-6.0, chi2 = 4.13, P= 0.04).
  
  
  CONCLUSIONS
  This study indicates that the FcgammaRIIIb-NA2 allele and possibly FcgammaRIIIa-158F could be associated with susceptibility to G-EOP in Japanese patients.
authors.affiliation: Department of Periodontology, Faculty of Dentistry, Niigata University, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kobayashi
authors.forename: N
authors.initials: N
authors.lastname: Sugita
authors.forename: W L
authors.initials: WL
authors.lastname: van der Pol
authors.forename: Y
authors.initials: Y
authors.lastname: Nunokawa
authors.forename: N A
authors.initials: NA
authors.lastname: Westerdaal
authors.forename: K
authors.initials: K
authors.lastname: Yamamoto
authors.forename: J G
authors.initials: JG
authors.lastname: van de Winkel
authors.forename: H
authors.initials: H
authors.lastname: Yoshie
mesh_terms: D000328:Adult; D010520:Aggressive Periodontitis / Q000208:ethnology / Q000235:genetics* / Q000276:immunology*; D000483:Alleles; D044466:Asian People / Q000235:genetics; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D010518:Periodontitis / Q000208:ethnology / Q000235:genetics / Q000276:immunology; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D011961:Receptors, Fc / Q000235:genetics*; D018709:Statistics, Nonparametric
chemical_list: D011961:Receptors, Fc