Relevance of immunoglobulin G Fc receptor polymorphism to recurrence of adult periodontitis in Japanese patients

Abstract

Polymorphonuclear neutrophil (PMN) phagocytic function has been shown to be impaired in some patients with periodontitis. PMN constitutively express members of two immunoglobulin G receptor (FcγR) classes: FcγRIIa (CD32) and FcγRIIIb (CD16). Both receptors exhibit genetically determined structural and functional biallelic polymorphisms, which have been shown to influence PMN phagocytic function. In this study, we assessed the relevance of these FcγR polymorphisms to susceptibility to adult periodontitis and recurrence rate. The distribution of FcγRIIa and FcγRIIIb genotypes of 100 Japanese patients with adult periodontitis during follow-up was compared to the distribution of genotypes in 105 race-matched healthy controls. No significant skewing of distributions of FcγRIIa and FcγRIIIb genotypes was observed between patients and controls. Notably, however, a significant overrepresentation of the FcγRIIIb-NA2 allotype was found in patients with disease recurrence (P < 0.05; odds ratio, 4.29; 95% confidence interval, 1.19 to 16.24). Moreover, the annual rate of recurrence was significantly higher in patients with the FcγRIIIb- NA2/NA2 and FcyRIIIb-NA1/NA2 genotypes than in FcγRIIIb-NA1/NA1 individuals (P < 0.05). FcγRIIa-R/R131 individuals also exhibited higher recurrence rates, though the difference was not statistically significant (P = 0.06). These results suggest that the FcγRIIIb-NA2 allotype represents a risk factor for recurrence of adult periodontitis.