Fc gamma receptor polymorphisms in relation to periodontitis

Objectives: Evidence suggests functional relevance for polymorphisms in Fcgamma R in relation to inflammatory and infectious diseases. The present aim was to investigate genetic polymorphisms in three Fcgamma R in relation to susceptibility and severity of periodontitis. Material and Methods: The study population consisted of 68 periodontitis patients and 61 controls (Northern European Caucasian background, mean ages 44 and 42 years, respectively). Among the patients, 12 subjects were diagnosed with aggressive periodontitis (AgP) and 56 individuals were diagnosed with chronic periodontitis (CP). Radiographic bone levels were scored for all teeth in the patients. Subjects were typed for the following genes (alleles): Fcgamma RIIa (R131 or H131), Fcgamma RIIIa (V158 or F158) and Fcgamma RIIIb (NA1 or NA2). Results: Hardy-Weinberg equilibrium criteria were fulfilled for the different genotypes at the three genes investigated. The frequency of the Fcgamma RIIIa-V158 allele in the patient population (53%) was higher than in the control group (39%) (OR 1.73 [1.06-2.85], p =0.034). The V158 carriage rate in AgP was even higher (63%). The frequency of the Fcgamma RIIa-H131 allele in the total periodontitis population was 58%; for AgP this was 79%, compared with 51% in the control population (OR 3.68 [1.29-10.5], p =0.013). Also, the frequency of the Fcgamma RIIa-H/H131 genotype was significantly higher in AgP patients than in controls (OR 9.07 [1.29-63.56], p =0.026, adjusted for smoking status and other potential confounders). Moreover, patients with the Fcgamma RIIa-H/H131 genotype had more severe radiographic bone loss than patients with the other Fcgamma RIIa genotypes. Conclusion: The current study of relative small sample size suggests that the Fcgamma RIIa-H/H131 genotype may be a putative susceptibility and severity factor, and the Fcgamma RIIIa-V158 allele a putative susceptibility factor for periodontitis in Northern European Caucasians. These results need further verification and the biological importance of these findings needs further investigation