CTLA-4基因启动子区-318位点基因多态性与SLE的相关性研究

目的：探讨细胞毒性T细胞相关分子—4(cytotoxic T lymphocyte antigen4，CTLA—4)基因启动子区—318位点基因多态现象在中国南方人群中的分布及与SLE易感性的关系。方法：提取外周静脉血有核细胞基因组DNA，以聚合酶饺反应—限制性片段长度多态性(polymerase chain reaction—restriction fragment length polymorphism,PCR-RFLP)方法检测180例SLE患者和140名正常对照组CTLA—4基因启动子区—318位点基因型。结果：SLE患者CTLA—4基因启动子区—318位点基因型频率分别为TT型1.1％、TC型41.1％和CC型58．8％，等位基因频率为T等位基因21.7％、C等位基因78.3％。SLE患者各种基因型频率及等位基因频率与对照组比较均无统计学意义。CTLA—4基因启动子区—318位点各基因型与SLE患者临床表现及实验室检查结果无相关关系。结论：SLE患者CTLA—4基因启动子区—318位点基因多态现象与SLE发病无关。

The polymorphism at position-318 in promoter of CTLA-4 gene in patients with systemic lupus erythematosus in southern China

Objective: To study the polymorphism at position 318 in promoter of cytotoxic T lymphocyte antigen 4 (CTLA 4) gene in systemic lupus erythematosus (SLE). Methods: The genotypes at position 318 in promoter of CTLA 4 gene were determined by polymerase chain reaction restriction fragment length polymorphism (PCR RFLP) method in 180 patients with SLE and 140 ethnically matched controls in southern China. Results: The frequencies of genotypes at position 318 in promoter of CTLA 4 gene in patients with SLE were 1.1% for TT, 41.1% for TC and 58.8% for CC, respectively. The frequencies of alleles at this position were 21.7% for T allele and 78.3% for C allele. The frequencies of genotypes and alleles in patients with SLE were not significantly different from those in controls. There was no correlation between the genotype and clinical manifestation or laboratory results. Conclusions: The polymorphism at position 318 in promoter of CTLA 4 gene is not associated with the susceptibility of SLE.