Fcγ receptor IIa, IIIa, and IIIb polymorphisms of systemic lupus erythematosus in Taiwan

Objective: To determine whether the distribution of Fcγ receptor IIa, IIIa, and IIIb polymorphisms confers a risk factor for disease susceptibility, and correlates with the clinical characteristics and serological parameters of patients with SLE in Taiwan. Methods: Genotyping of Fcγ receptors IIa H/R131, IIIa F/ V158, and IIIb NA1/NA2 was performed in 302 patients with SLE and 311 healthy blood donor controls. The distribution of Fcγ receptor IIa, IIIa, and IIIb genotypes in patients and controls was analysed. Frequencies of three Fcγ receptor polymorphisms were also compared between lupus patients with and without different clinical manifestations and autoantibodies. Results: No significant skewing in the distribution of Fcγ RIIa H/R131, Fcγ RIIIa F/V158, and Fcγ RIIIb NA1/NA2 was found between patients and controls in Taiwan. The following clinical associations were found: Fcγ RIIIb NA1/NA1 protected against neuropsychiatric lupus (p=0.028) but conferred susceptibility to discoid rash (p<0.005); increased Fcγ RIIIa V/V158 was associated with infections (p=0.039); increased Fcγ RIIa H/H131 was associated with earlier onset of lupus (p=0.01). Conclusion: Fcγ receptor IIa, IIIa, and IIIb polymorphisms may be responsible for the development of distinct manifestations of lupus patients in Taiwan, but there is no significantly skewed distribution in the susceptibility to lupus as a whole.