Song Y W, Han C W, Kang S W, Baek H J, Lee E B, Shin C H, Hahn B H, Tsao B P
Seoul National University Hospital, Korea.
Arthritis Rheum. 1998 Mar;41(3):421-6. doi: 10.1002/1529-0131(199803)41:3<421::AID-ART7>3.0.CO;2-S.
Abnormal immune complex clearance is a feature of systemic lupus erythematosus (SLE). Polymorphisms of the Fc gamma receptor type IIa (Fc gammaRIIa) genes (the receptor binds IgG2 and IgG3) are important disease susceptibility factors in some populations. This study sought to determine the effects of these polymorphisms among Korean patients with SLE.
Polymerase chain reaction of genomic DNA and allele-specific oligonucleotide hybridization were used to determine Fc gammaRIIa genotypes in Korean patients with SLE and healthy control subjects. Clinical manifestations were analyzed in each patient and correlated with the genotypes.
Among the 73 SLE patients, there was an abnormal distribution of Fc gammaRIIa alleles when compared with 64 controls: 11.0% of the SLE patients were homozygous for Fc gammaRIIa-H131 compared with 34.4% of the controls (odds ratio [OR] 0.20, 95% confidence interval [95% CI] 0.04-0.95, chi2 = 5.7, P = 0.01699). The allelic frequency of Fc gammaRIIa-H131 was significantly lower in the SLE patients than in the controls (49.3% versus 63.3%; P = 0.02019), and it was also significantly lower in lupus patients with nephritis compared with the normal population (OR 0.53, 95% CI 0.29-0.95, chi2 = 5.15, P = 0.02330), but was not significantly lower in lupus patients without nephritis (P = 0.13663 versus controls). Clinically, the level of proteinuria was significantly higher in the lupus nephritis patients who had R/R131 than in those who had H/H131 or R/H131.
An abnormal distribution of Fc gammaRIIa polymorphisms was associated with SLE in Korean patients. There was a significant decrease in the Fc gammaRIIa-H/H131 genotype and H131 allelic frequency in SLE patients, particularly in those with nephritis. This suggests that the H131 allele confers some protection from SLE in this population.
异常免疫复合物清除是系统性红斑狼疮（SLE）的一个特征。Fcγ受体IIa（FcγRIIa）基因多态性（该受体可结合IgG2和IgG3）在某些人群中是重要的疾病易感因素。本研究旨在确定这些多态性对韩国SLE患者的影响。
采用基因组DNA聚合酶链反应和等位基因特异性寡核苷酸杂交技术，对韩国SLE患者和健康对照者的FcγRIIa基因型进行测定。分析每位患者的临床表现，并将其与基因型进行关联。
在73例SLE患者中，与64例对照相比，FcγRIIa等位基因分布异常：11.0%的SLE患者为FcγRIIa-H131纯合子，而对照为34.4%（优势比[OR]0.20，95%置信区间[95%CI]0.04 - 0.95，χ2 = 5.7，P = 0.01699）。SLE患者中FcγRIIa-H131的等位基因频率显著低于对照（49.3%对63.3%；P = 0.02019），与正常人群相比，狼疮肾炎患者中该等位基因频率也显著降低（OR 0.53，95%CI 0.29 - 0.95，χ2 = 5.15，P = 0.02330），但无肾炎的狼疮患者中该等位基因频率降低不显著（与对照相比P = 0.13663）。临床上，R/R131的狼疮肾炎患者蛋白尿水平显著高于H/H131或R/H131的患者。
在韩国患者中，FcγRIIa多态性分布异常与SLE相关。SLE患者中FcγRIIa-H/H131基因型和H131等位基因频率显著降低，尤其是肾炎患者。这表明H131等位基因在该人群中对SLE有一定的保护作用。
