【作者】 田强；

【导师】 赵堪兴；

【作者基本信息】 天津医科大学 ， 眼科学， 2004， 博士

【摘要】 背景 青光眼是现今主要的致盲疾病之一。估计全球约有6,700,000人因患青光眼而双目失明。世界范围内,原发性开角型青光眼(POAG)是最常见的亚型,在长期的医学实践中,人们发现很多青光眼有明显的遗传倾向。最近一些研究显示某些基因的缺陷是导致青光眼的原因。在众多的研究结果中,最有意义的是将POAG致病的相关基因定位于染色体1q21至1q31之间。位于该区域的小梁网糖皮质激素诱导反应蛋白(trabecular meshwork induced glucocorticoid response protein,TIGR)基因(OMIM:~*601652)也被证实与POAG患者的发病有关,并发现多个突变点。但是目前致病性TIGR基因突变的报道大多数源自白人和黑人,全球范围内有关中国人TIGR致病性基因突变的报导很少。 目的: 探讨一中国人原发开角型青光眼家系的TIGR基因缺陷及其突变。 方法: (1) POAG家系的临床及遗传学的研究 对1996-2004年临床中所接触到的POAG患者及其家属进行家族遗传资料的询问及全面的眼科检查。临床检查内容主要包括:视力和屈光检查、裂隙灯检查、直接或间接眼底镜检查、视野检查(Octopus型全自动视野分析仪,美国)、眼压、房角镜检查以及视网膜断层仪(Retina Tomograph Ⅱ,Heidelberg Engineering,德国)摄影等。根据临床检查结果将家系成员分为青光眼患者、青光眼可疑者和正常者三类。POAG患者的诊断标准为:(1)特征性青光眼更多还原

【Abstract】 Background:Primary open angle glaucoma (POAG) is one of the leading causes of blindness worldwide. Defects in trabecular -meshwork inducible glucocorticoid response. (TIGR) gene (OMIM: ~*601652) have been shown to be associated with POAG. Many mutations in TIGR gene have been reported. However, in the literature, descriptions of disease-causing TIGR mutations in Chinese population are few.Purpose:To determine the possible TIGR molecular genetic defect underlying POAG in China and to identify the pathogenic mutation causing the disease.Methods:(1) Clinical and genetic study of the POAG familyA large POAG family was chosen from many POAG families we investigated during the last 8 years to be complete studied in thisprogram. The majority of 1 branch of this large Chinese POAG family was personally examined by two senior ophthalmologists. The diagnoses were made by both doctors according to the signs of elevated intraocular pressure (IOP), glaucomatous optic neuropathy and glaucomatous visual field defect. (2) Molecular genetic study of the POAG family1. Isolation of the genomic DNA: genomic DNA was extracted from the family members’ blood by using DNA Isolation Kits for Mammalian Blood(Roche Biochimical, Inc).2. PCR primer design: PCR primers were designed to amplify all coding sequences of the TIGR gene plus the flanking sites.3. PCR amplification: PCR amplification was performed in a 50ul or 20ul volume4. Purification of the PCR products: PCR products were purified using Gel purification Kits(Omega, USA)5. Mutation screening: 100 normal control subjects were screened by single strand conformational polymorphism analysis for the mutation.Results:(1) Genetic analysis of the POAG familyThis 5 generation family was composed of 62 members, including 46 males and 16 females. There were 7POAG patients, 3 glaucoma suspects and 10 normal subjects among the family members who donated their blood samples. All POAG patients had elevated intraocular pressures that could not be adequately lowered by medications. Filtering surgery was performed on 6 of 7 affected family members. The remaining one has reached the late stage of POAG.(2) Molecular genetic analysis of the POAG familyA novel disease-causing missence mutation T455K in the third exon of the TIGR gene was identified in all affected family members, all glaucoma suspects and 4 individuals who have not shown apparently signs of glaucoma. None of the subjects without the mutation had glaucoma. Affected individuals with the T455K mutation showed variable onset between 26-59 years of age. The T455K mutation in TIGR gene was not found in the normal controls. A previously reported polymorphism 730+35 (A>G) in the second intron of the TIGR gene was detected in 4 individuals.Conclusion:The novel TIGR sequence alteration T455K that was highly更多还原