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

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 (Fc gammaR) classes: Fc gammaRIIa (CD32) and Fc gammaRIIIb (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 Fc gammaR polymorphisms to susceptibility to adult periodontitis and recurrence rate. The distribution of Fc gammaRIIa and Fc gammaRIIIb 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 Fc gammaRIIa and Fc gammaRIIIb genotypes was observed between patients and controls. Notably, however, a significant overrepresentation of the Fc gammaRIIIb-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 Fc gammaRIIIb-NA2/NA2 and Fc gammaRIIIb-NA1/NA2 genotypes than in Fc gammaRIIIb-NA1/NA1 individuals (P < 0.05). Fc gammaRIIa-R/R131 individuals also exhibited higher recurrence rates, though the difference was not statistically significant (P = 0.06). These results suggest that the Fc gammaRIIIb-NA2 allotype represents a risk factor for recurrence of adult periodontitis.