中国南方人群Fc受体γ链基因3′端非翻译区基因多态性与系统性红斑狼疮的关系

Polymorphism in 3' untranslated region of Fc receptor γ chain gene in patients with systemic lupus erythematosus in southern China

目的 探讨Fc受体γ链基因3’端非翻译区(3’-UTR)基因多态性现象在中国南方人群中的分布及与系统性红斑狼疮(SLE)易感性和临床表现的关系。方法 采用PCR-限制性片段长度多态性(RFLP)方法检测180例SLE患者和140例正常对照组Fc受体γ链基因3’-UTR 3847及3804位点基因型。结果 SLE患者Fc受体γ链基因3’-UTR 3847位点CC基因型频率(8.9％)及C等位基因频率(32.7％)较对照组(2.9％及23.6％)明显升高(P<0.025);而TT基因型频率(43.3％)及T等位基因频率(67.3％)较对照组(55.7％及76.4％)明显降低(P<0.025)。SLE伴狼疮肾炎(LN)患者CC基因型频率及C等位基因频率较不伴LN的患者明显升高(P<0.05及P<0.025)。对Fc受体γ链基因3’-UTR 3804位点基因型的研究显示,在全部病例和对照组中仅1例SLE患者为TG型,其余均为TT型。结论 SLE患者Fc受体γ链基因3’-UTR 3847位点C等位基因与SLE发病及LN的发生有关。3804位点基因多态性现象在中国南方人群中少见,该位点的多态性与SLE发病无关。

Objective To investigate the association between the polymorphisms in 3' untranslated region (3'-UTR) of Fc receptor 7 chain gene and systemic lupus erythematosus(SLE) . Methods The genotypes at position 3847 and 3804 in 3'-UTR of Fc receptor γ chain 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 CC genotype (8. 9% ) and C allele (32. 7% ) at position 3847 in patients with SLE were significantly higher than those in controls (2.9% and 23.6%, respectively), whereas, the frequencies of TT genotype (43.3% ) and T allele (67. 3% ) in patients with SLE were remarkably lower than those in controls (55. 7% and 76. 4%, respectively) ( P < 0. 025). The CC genotype and C allele at position 3847 was strongly associated with lupus nephritis in SLE patients ( P < 0. 05 and P < 0. 025, respectively) . At position 3804, only one SLE patient with TG genotype was detected while other patients and all of the controls were found with TT genotype. Conclusions C allele at position 3847 in 3'-UTR of Fc receptor gene probably contributes to the susceptibility of SLE and may play a role in the occurrence of lupus nephritis. The polymorphism at position 3804 is rare in southern Chinese individuals and this polymorphism has no relationship with the susceptibility of SLE.