Association of rheumatoid factor production with FcγRIIIa polymorphism in Taiwanese rheumatoid arthritis

Fc gamma receptors (Fc gamma R) impact upon the development of inflammatory arthritis through immune complex stimulation and proinflammatory cytokine production. Fc gamma RIIa, Fc gamma R Iota Iota Iota a and FcR gamma IIIb polymorphisms were genotyped in 212 rheumatoid arthritis (RA) patients and 371 healthy control subjects using an allelic-specific polymerase chain reaction (PCR). No significant skewing in the distribution of Fc gamma RIIa H/R131, Fc gamma RIIIa F/V158 and Fc gamma RIIIb NA1/NA2 was found between RA patients and healthy control subjects. However, a significant skewing distribution of the Fc gamma RIIIa F/V158 polymorphism was observed between rheumatoid factor (RF)-positive versus RF-negative RA patients (P = 0.01). The low-affinity Fc gamma RIIIa F158 allele seems to have a protective role in RF production, in comparison with the Fc gamma RIIIa V158 allele (P = 0.004; OR = 0.485; 95% CI: 0.293-0.803). A high frequency of Fc gamma RIIIa F/F158 was identified in RA patients with negative RF compared with RF-positive patients (for FF158 versus FV158 + VV158; P = 0.002; OR = 0.372; 95% CI: 0.194-0.713). In addition, no association was found between Fc gamma RIIa H/R131, Fc gamma Rho IIIa F/V158 and Fc gamma RIIIb NA1/NA2 polymorphisms and other clinical parameters. The results of this study suggest that three activating Fc gamma Rs polymorphisms lack association with RA but Fc gamma IIIa F/V158 polymorphism may influence RF production and IgG RF immune complex handling in Taiwanese RA patients.