【作者】 马灵军；

【导师】 苏冠方；

【作者基本信息】 吉林大学 ， 眼科学， 2008， 博士

【摘要】 目的:研究补体因子H Y402H、B因子R32Q、L9H、LOC387715 A69S、ERCC6C-6530G单核苷酸多态性与年龄相关性黄斑变性(AMD)的相关性,通过病例-对照分析论证5个基因变异为AMD致病的相关性因素。方法:通过抽取病例组及对照组的外周血,提取基因组DNA,聚合酶链反应(Polymerase Chain Reaction,PCR)扩增目的基因片断并进行PCR-RFLP法、SNaPshot测序,检测基因变异。运用统计学软件Epicalc2000对所有等位基因频率及基因型进行统计学分析。结果:1.携带补体因子H Y402H(rs1061170 T＞C)至少一个C等位基因的AMD患者的患病风险比对照组增高,(OR值为2.75,95%CI=2.00～3.78);携带该基因的个体患湿性型AMD的风险比患干性型AMD的风险高(湿性型AMD OR值为4.5,95%CI=2.9～7.0;干性型AMD OR值为1.93,95%CI=1.30～2.85)。2.携带LOC387715/ARMS2 A69S(rs10490924 G＞T)至少一个T等位基因的AMD患者的患病风险比对照组增高,(OR值为3.00,95%CI=2.07～4.37);同时携带LOC387715/ARMS2 A69ST等位基因与补体因子H Y402H C等位基因的个体患AMD的风险更高(OR值为34.67,95%CI=3.93～305.94)。3.携带B因子危险等位基因的AMD患者的患病风险与对照组无差异(R32Q的OR值为0.51,95%CI=0.21～1.23,p=0.13;L9H的OR值为0.81,95%CI=0.34～1.94,P=0.64)。4.携带ERCC6基因危险等位基因G的AMD患者的患病风险与对照组无差异(OR值为0.84,95%CI=0.58～1.21,P=0.35)。结论:补体因子H与LOC387715为AMD的危险致病因子;B因子与AMD的发病无相关性;ERCC6基因可能与AMD的发病相关。更多还原

【Abstract】 Age-related Macular Degeneration(AMD)is the most common form of irreversible blindness among patients 50 years and older in developed coutries such as American,Japan and Australia.The clinical hallmark of AMD is the appearance of drusen,localized deposits lying between the basemeng membranes of the retinal pigment epithelium(RPE)and Bruch membrane.The progressive degeneration of central part of retina called the macula leads to the loss of central vision.It is estimated that by the year 2020,the number of individuals having AMD will increased to 3 million.At present,50 million persons are diagnosed as AMD all over the world.AMD is also an important cause of visual impairment of the elderly 60 years and older in China.The pathogenesis of AMD remains unclear.The contemporary view is that AMD is a multifactor disorder stemming from the interaction of multiple genetic factors and environmental risk factors such as advanced age,light exposure,oxidative damage.In 2005,Seddon et al reported that genetic factors play a substantial role in the etiology of AMD and associated macular characteristics,explaining 46%to 71%of the variation in the overall severity of the disease.Twin and population-based aggregation studies have also implicated a hereditary component in the disorder.Recently,a number of studies have identified associations between AMD and some candidate genes.AimsTo investigate the associations between several coding variants,Y402H,in the complement factor H gene(CFH),L9H and R32Q in Complement Factor B(BF),A69S in LOC387715 and C-6530G in ERCC6 and AMD.The interactions of the gene-gene and phenotype-genotype were also investigated.MethodsOne hundred twenty-five South Australian patients with AMD and two hundred seventeen well characterized normal individuals were enrolled in the study.Genomic DNA from white blood cells was extracted.Y402H polymorphism in CFH;L9H、R32Q polymorphisms in BF;A69S polymorphism in LOC387715;and C-6530G polymorphism in ERCC6 were amplified by polymerase chain reaction(PCR),SNaPshot and enzyme digest based assay were developed for rapid PCR based genotyping of the CFH Y402H and ERCC6 C-6530G variants.The L9H polymorphism and R32Q polymorphism in BF,A69S polymorphism in LOC387715 were determined by PCR-restriction fragment length polymorphism analysis.The association between the genetic polymorphisms and the disease was examined by software Epicalc2000.Results1.The frequency of the risk allele,1277C was 65.2%in AMD patients compared with 40.6%in controls(P=0.00000000053).Genotype frequency differed significantly between the two groups(1277TT15.2%, 1277TC39.2%,1277CC45.6%in the AMD group;1277TT36.4%, 1277TC46.1%,1277CC17.5%in the control group;P=0.000000017).On subgroup analysis.The 1277C allele significantly increased the risk for neovascular AMD(wet AMD OR=4.5;95CI=2.9～7.0;dry AMD OR=1.93,95%CI=1.3～2.85)。2.LOC387715 A69S polymorphism was related to AMD with odds ratio (ORs)of 2.64(95%CI=1.82～3.83).The effect was not stronger for wet AMD(OR=2.55;95CI=1.62～4.00)compared with dry AMD(OR= 2.73,95%CI=1.77～4.23)relative to no progression for the homozygous risk state.The disease odds ratio is 34.5(95%CI=3.93～305.94)conferred by homozygosity for risk alleles at both CFH and LOC387715 when compared with the baseline non-risk genotype.3.The frequency of risk alleles,L9H and R32Q in BF was 4.5%in cases and 5.4%in controls(P=0.64)and 5.7%in cases and 10.6%in controls(P =0.13),respectively.4.The frequency of the risk allele G in ERCC6 was 51.8%in AMD patients compared with 47.4%in controls(P=0.35).Genotype frequency was difference between the two groups(CC22.3%,GC51.8%,GG25.9%in the AMD group;CC18.8%,GC67.5%,GG13.7%in the control group;P =0.03).Conclusions1.Y402H in the gene CFH is associated with dry and wet AMD.2.A69S in the gene LOC387715 is related to AMD,a disease odds ratio of 34.5 conferred by homozygosity for risk alleles at both CFH and LOC387715 when compared with the baseline non-risk genotype.3.There is no association between BF and AMD.4.The SNP C-6530G of ERCC6 maybe associatied with AMD.更多还原