摘要目的 观察重庆地区汉族人群增生型糖尿病视网膜病变(PDR)患者C5基因单核苷酸多态性(SNP)的遗传易感性.方法 400例临床检查确诊的2型糖尿病(T2DM)患者为病例组,选取年龄、性别匹配的正常人群600名为正常对照组.病例组采用早期糖尿病视网膜病变治疗研究组诊断标准对眼底病变进行判断,其中PDR患者8例.病例组、正常对照组受试者均为汉族.通过连锁不平衡分析筛选出C5基因与免疫相关的代表性SNP位点rs2269067、rs7040033、rs7027797,在上述3个SNP位点附近根据TagSNP选择1个SNP位点rs1017119,最终4个SNP位点纳入研究.抽取受试者外周静脉血,提取DNA.采用限制性片段长度多态性聚合酶链反应对SNP基因进行分型;酶链免疫吸附测定法检测血浆中补体C5蛋白浓度.结果 病例组PDR患者与正常对照组受试者C5基因rs7040033、rs1017119、rs7027797位点G、CC、CG、GG基因型、等位基因频率比较,差异无统计学意义(P＞0.05).病例组PDR患者血浆中补体C5蛋白浓度表达较正常对照组受试者明显升高,差异有统计学意义(P=0.0004);C5基因rs2269067位点GG基因型PDR患者血浆中补体C5蛋白浓度表达较CG、CC基因型PDR患者增高,差异有统计学意义(P=0.003、0.001).病例组PDR患者C5基因rs2269067位点GG基因型频率较正常对照组受试者明显增高,差异有统计学意义(Pc=3.4×10-5,比值比=1.87,95％可信区间为1.43～2.44;P=3.1×10-6);G、CC、CG基因型、等位基因频率比较,差异无统计学意义(P=1.4×10-4、1.000、1.0×10-6).结论 C5基因rs2269067位点GG基因型与重庆地区T2DM患者PDR发病相关.

abstractsObjective To observe the genetic predisposition of complement C5 gene polymorphisms in proliferative diabetic retinopathy (PDR) in Chongqing Han population.Methods 400 type 2 diabetes (T2D) patients (case group) and 600 age-and sex-matched healthy controls (control group) were enrolled in this study.There were 8 PDR patients in case group.All the subjects were Han ethnic people.The immune-related representative SNP locus of C5 gene including rs2269067,rs7040033,rs7027797 were screened by linkage disequilibrium analysis.Locus rs1017119 was selected by TagSNP and was around the above three loci.Subjects' peripheral venous blood was collected and DNA was extracted.Genotyping was examined by PCR-restriction fragment length polymorphism method.The level of C5 plasma protein was measured by enzyme-linked immunoabsorbent assay.Results The frequency of GG genotype of rs2269067 was significantly increased in PDR patients in cases group compared with controls (Pc=3.4 × 10-5,OR=1.87,95％CI=1.43-2.44;P=3.1 × 10-6).There was no differences in frequency of G,CC and CG genotype of rs2269067 between two groups (P=1.4 × 10-4,1.000,1.0 × 10-6).There were no differences in frequency of G,CC,CG,GG genotype of rs7040033,rs1017119,and rs7027797 between two groups (P＞0.05).The production of C5 plasma protein was significantly increased in case group as compare with control group (P=0.0004).An increased production of C5 plasma protein was observed in rs2269067 GG genotype cases compared to CG or CC cases (P=0.003,0.001).Conclusion C5 rs2269067 GG genotype may be associated with the PDR of T2D in Chongqing Han population.