FcγRIIB Gene Polymorphisms Are Associated with Disease Risk and Clinical Manifestations of Systemic Lupus Erythematosus in Koreans

FcγRIIB Gene Polymorphisms Are Associated with Disease Risk and Clinical Manifestations of Systemic Lupus Erythematosus in Koreans

JA-YOUNG JEON,¹ KEON-YOUNG KIM,¹ BONG-SIK KIM,¹ JU-YANG JUNG,¹ HYOUN-AH KIM¹ and CHANG-HEE SUH¹

¹Department of Rheumatology and BK21 Division of Cell Transformation and Restoration, Ajou University School of Medicine, Suwon, Korea

Systemic lupus erythematosus (SLE) is chronic autoimmune disease with various autoantibodies, which are involved in tissue damage. Fc gamma receptors (FcγRs) bind the constant region of the immunoglobulin G and transmit stimulatory or inhibitory signal to immune cells. The FcγR genes map to 1q23, a susceptible locus for SLE. We have screened single nucleotide polymorphisms (SNPs) in one of FcγR gene, FcγRIIB, which is the only inhibitory receptor, after considering gene map and reported SNPs. There were 3 SNPs in FcγRIIB: 10849 T>C (rs1050501) in exon 5 and 10950 T>G (rs6666965) and 11045 G>T (rs12117530) in intron 5 in Koreans. The frequency of the minor allele (T) of rs12117530 was significantly higher in SLE patients (50 patients, 20.4%) than healthy controls (17 patients, 12%, p = 0.041). Leukopenia occurred more frequently in SLE patients carrying the minor allele (T) of rs12117530 (p = 0.032). Among 5 haplotypes, the frequency of decreased complement was significantly lower in SLE patients with haplotype 1 [TTG] (p = 0.045). Nephritis, lymphopenia and anti-dsDNA antibody were significantly less frequent in SLE patients with haplotype 2 [TGG] (p = 0.046, p = 0.018, p = 0.002, respectively). The frequency of thrombocytopenia and anti-dsDNA antibody was significantly higher in SLE patients with haplotype 3 [CTG] (p < 0.001, p = 0.04, respectively). These data reveal that genetic polymorphisms within FcγRIIB are associated with disease susceptibility and phenotypes of SLE in Koreans. Furthermore, FcγRIIB rs12117530 polymorphism (T allele) may be an important risk factor in SLE.

keywords —— Keywords: immunoglobulin G receptor; phenotype; risk factor; single nucleotide polymorphism; systemic lupus erythematosus

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Tohoku J. Exp. Med., 2015, 236, 185-191

Correspondence: Chang-Hee Suh, M.D., Ph.D., Department of Rheumatology and BK21 Division of Cell Transformation and Restoration, Ajou University School of Medicine, 164 Worldcup-ro, Yeongtong-gu, Suwon 443-380, Korea.

e-mail: chsuh@ajou.ac.kr