Analysis of the association between Fc receptor family gene polymorphisms and ocular Behçet's disease in Han Chinese.

Fc receptors are known to have a pivotal role in the initiation and regulation of many immunological and inflammatory processes. This study aimed to investigate the association of Fc receptor family gene polymorphisms with ocular Behçet's disease (BD) in Han Chinese. A two stage case-control study was performed in 1022 BD cases and 1803 healthy controls. Twenty-three SNPs were genotyped using the MassARRAY system (Sequenom), TaqMan SNP Genotyping Assay and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The expression of FCGR3A was examined by real-time PCR and cytokine production was measured by enzyme linked immunosorbent assay (ELISA). A significantly higher frequency of the FCGR3A/rs428888 CT genotype (Pc = 1.96 × 10-7 , OR = 1.897) and a lower frequencies of CC genotype and C allele (Pc = 1.96 × 10-7 , OR = 0.527; Pc = 7.22 × 10-7 , OR = 0.554 respectively) were found in ocular BD as compared with controls. Functional experiments showed an increased FCGR3A expression (P = 0.005) and increased cytokine protein expressions of MCP-1, IL-1β and TNF-α by LPS stimulated PBMCs in CT carriers of FCGR3A rs428888 compared to CC carriers (P = 0.034; P = 0.025; P = 0.04; respectively). Our findings demonstrate that FCGR3A/rs428888 confers genetic susceptibility for ocular BD in Han Chinese.