Single Nucleotide Polymorphism rs10919543 in FCGR2A/ FCGR3A Region Confers Susceptibility to Takayasu Arteritis in Chinese Population

Background： Takayasu arteritis （TA） is a rare inflammatory arteriopathy of unknown etiology. The aim of this study was to investigate the genetic susceptibility to TA in a Chinese population. Methods： Four single nucleotide polymorphisms （SNPs） those locate in the IL12B region （rs56167332）, the MLX region （rs665268）, the FCGR2A/FCGR3A locus （rsi0919543）, and the HLA-B/M1CA locus （rs12524487）, associated with TA in different population, were genotyped in 123 Chinese TA patients and 147 healthy controls from January 2013 to August 2014. A Chi-square test was used to test for genotype/allele frequencies variants. Results： Among the four SNPs, rs 10919543 was found to be significantly associated with TA in the studied population. The GG genotype of rs 10919543 at the FCGR2A/FCGR3A locus is a high risk factor （odds ratio [OR] = 6.532, 95% confidence interval [C1] = 2.402 - 17.763, P 〈 0.001 ） for TA. Among TA patients, the level of eosinophil granulocytes （Eos） in the peripheral blood was observed to be higher in the GG group of rs 10919543 （n = 23, Eos = 0. I 1 [0.08, 0.17] x 109/L） than the GA ＋ AA group （n = 100, Eos = 0.08 [0.05, 0.13] 10/L, P = 0.028）. No correlation between the genotypes of the other three SNPs and TA patients was observed. Conclusions： Our findings revealed unique genetic pattern in Chinese TA patients that may be partly responsible for the higher risk of TA in this population. FCGR2A/FCGR3A-related immune disorder might contribute to the etiology of TA.