原发性先天性青光眼患者CYP1B1突变的研究

目的:了解原发性先天性青光眼患者致病基因CYP1B1(Cytochrome P450 family 1 subfamily B polypeptide 1)的变异情况.方法:采用高分辨率熔解(high-resolution melting,HRM)方法,分析20例原发性先天性青光眼患者的CYP1 B1基因热点突变区,同时采用测序的方法验证HRM的检测结果.结果:检出g.6767C＞T(p.D449D)变异2例,g.2527C＞G(p.R48G)变异1例,两种变异共存者1例.结论:在CYP1B1基因突变筛查方法中,HRM具有高度的灵敏性和特异性,可用于筛查原发性先天性青光眼.PCG的原因可能与g.6767C＞T(p.D449D)和g.2527C＞G(p.R48G)的变异有关;两种变异共存者可能导致更严重的PCG.     

中国人原发性先天性青光眼患者CYP1B1基因突变分析

原发性先天性青光眼(primary congenital glaucoma,PCG),是一种严重危害儿童视力的致盲性眼病,与遗传有一定关系。为探讨中国人PCG与CYP1B1基因的关系,我们对7例PCG患者的CYP1B1基因进行分析,现报告如下。1材料与方法1.1病例收集在广州市儿童医院眼科就诊的表型为PCG的患者7例,抽取静脉血5mL,EDTA抗凝。所有标本间均无任何血缘关系。1.2主要试剂和仪器DNA抽提试剂盒、dNTPs、Taq酶(美国Fermentas公司),100bp DNA Markers、EB替代品(广州威佳公司)。采用Biometra UNOⅡ型PCR仪(德国Biometra公司)。1.3基因组DNA的制备按…     

湖北地区汉族原发性先天性青光眼患儿CYP1B1基因突变分析

目的研究湖北地区汉族原发性先天性青光眼(primary congenital glaucoma,PCG)患儿CYP1B1基因的突变情况。方法用苯酚-氯仿法从38例原发性先天性青光眼患儿的全血细胞中提取基因组DNA。然后通过聚合酶链反应-单链构象多态性(single-strand conformation polymorphism,PCR-SSCP)银染色法检测CYP1B1基因第2、3外显子的突变情况。结果5例PCG患儿检出CYP1B1基因第3外显子异常DNA片段条带,经测序分析证实为7990C→T,未发现第2外显子存在基因突变。结论CYP1B1基因具有明显的遗传异质性。应用PCR-SSCP技术可初步筛查原发性先天性青光眼患儿CYP1B1基因突变。     

原发性先天性青光眼的遗传学研究进展

原发性先天性青光眼作为严重威胁婴幼儿视力发育的眼病,其遗传倾向受到关注,目前GLC3A,GLC3B和GLC3C三个相关候选基因已经定位。CYP1B1是目前仅找到的先天性青光眼的致病基因,其突变和功能的研究成为热点。本文就先天性青光眼的分子遗传学研究进展及其与CYP1B1的关系作一综述。     

CYP1B1突变与眼科疾病

细胞色素P4501B1（CYP1B1）是人体重要的代谢酶，本文从生化结构、细胞定位、遗传多态等方面对P4501B1基因（CYP1B1）进行了综述，并重点讨论了该基因的突变在原发性先天性青光眼、青少年型青光眼、Peters异常等眼病中的可能致病机制。     

CYP1B1基因缺失小鼠在高糖皮质激素环境下对青光眼的易感性

目的观察高浓度糖皮质激素对CYP1B1^-/-小鼠青光眼易感性的影响。方法采用成年CYP1B1^-/-小鼠作为实验模型,以同龄C57BL／6J小鼠作为对照。每3天结膜下注射0．04mL倍他米松,用Tonopen眼压（IOP）笔每周定期测定小鼠IOP,于第一次给药前,给药后4、8、12周分别摘除眼球,制备石蜡切片,光学显微镜下观察小鼠视网膜形态和厚度,采用TUNEL法检测视网膜神经节细胞（RGCs）的凋亡。结果与给药前相比,2组小鼠给药后4、8、12周的IOP均较前升高,差异有统计学意义（P〈0．05）;CYP1B1^-/-小鼠的IOP在给药后8周、12周较C57BL／6J小鼠显著升高,差异有统计学意义（P〈0．05）。随着倍他米松注射时间的推移,2组小鼠视网膜纤维层均变薄,各时间组的总体差异有统计学意义（P〈0．05）;且CYP1B1^-/-小鼠视网膜纤维层厚度在给药后8周、12周较C57BL／6J小鼠显著变薄,差异有统计学意义（P〈0．05）。2组小鼠RGCs凋亡的速度与给药前相比均显著增加,差异有统计学意义（P〈0．05）;且CYP1B1^-/-小鼠与C57BL／6J小鼠相比结果更为显著（P〈0．05）。结论在高浓度糖皮质激素的诱导下,CYP1B1^-/-小鼠对青光眼的易感性增加。     

原发性先天性青光眼的分子遗传学研究新进展

原发性先天性青光眼(primary congenitalglauco—ma，PCG)是一种遗传性致盲眼病。其防治关键在于揭示PCG致病基因，实现基因诊断和治疗。近年来的分子遗传学研究确定CYPlBl基因为PCG致病基因之一。本文对CYPlBl基因突变及其遗传特点作一综述，旨在为进一步研究提供参考。     

原发性先天性青光眼临床治疗研究

目的：观察并分析外路小梁切开联合小梁切除术治疗原发性先天性青光眼的临床疗效。 方法：收集原发性先天性青光眼患者51例89眼,应用外路小梁切开联合小梁切除术进行治疗,观察术后眼压、角膜横径、杯/盘比值、滤过泡情况及手术并发症并分析其临床疗效。 结果：术后平均随访（15.21±6.50）mo,术后1,6,12mo手术成功率分别为97%,90%,90%。术后平均眼压较术前显著降低(P<0.01);杯/盘比值较术前明显减小（P<001）;角膜横径手术前后差异无显著意义（P=0.495）;手术失败者角膜横径较术前增大（P<0.05）。手术并发症主要有不同程度的前房出血和术后浅前房等。 结论：外路小梁切开联合小梁切除术是治疗原发性先天性青光眼安全有效的手术方式之一     

原发性先天性青光眼CYP1B1基因新变异

目的 探讨CYP1B1基因变异在湖南地区原发性先天性青光眼患者中的分布.方法 病例对照研究.收集来自湖南地区的13例原发性先天性青光眼患者的临床资料进行分析,对13例患者的CYP1B1基因编码外显子进行直接测序和聚合酶链反应-限制性内切酶技术检测.结果 13例原发性先天性青光眼患者中,有1例发现一种基因新突变(c.C319G,L107V),是位于外显子2的错义突变.100例正常人中未见L107V突变.同时发现已报道的4种单核苷酸多态位点,分别为R48G、A119S、V432L、D449D.结论 CYP1B1基因L107V突变可能是导致湖南地区原发性先天性青光眼患者的致病原因之一.     

原发性先天性青光眼分子遗传学研究进展

原发性先天性青光眼（primarycongenital aucoma,PCG）是一种发生于婴幼儿的遗传性致盲性眼病,也是先天性青光眼中最常见的类型,遗传因素为该病的主要致病原因,目前报道的与PCG相关的候选基因为CYPIBl、LTBP2和MYOC,并对这些基因的遗传方式、突变筛查及突变后的基因结构、功能改变等方面做了大量研究。然而,上述基因突变并不能解释所有PCG患者的发病机制,因此,发现新的致病基因和突变位点将成为研究工作者关注的焦点。f国际眼科纵览,2012,36：293—297）     

Overview of Cytochrome P450 1B1 gene mutations in patients with primary congenital glaucoma

The objective of this study was to investigate the distribution of mutations in the Cytochrome P450 1B1 gene (CYP1B1) in patients with primary congenital glaucoma (PCG) among different populations. All identifiable original studies on CYP1B1 gene mutations of patients with PCG were reviewed. Finally, DNA mutations within the CYP1B1 gene were identified in 542 patients with PCG according to 52 scientific articles and 147 distinct mutations were found. The 3987G>A (G61E) missense mutation is a founder mutation in Middle Eastern population, responsible for 45.52% of CYP1B1 mutations. In Gypsies, missense mutation 7996G>A (E387K) seems to be a founder mutation, accounting for 79.63% of CYP1B1 mutations. It seems that there is no founder mutation in Asian or Caucasian population, but also accumulates in some spots. Mutations 7927G>A (V364M), 7990C>T (L385F) and 8006G>A (R390H) are common in Asian population. In Caucasians, 7940G>A (R368H), 8037dup10, 8006G>A (R390H), 7901del13, 4340delG, 3987G>A (G61E), 7996G>A (E387K), 4490G>A (E229K) and 8005C>T/A (R390C/S) are common mutations. The findings suggest that ethnic differences and the geographical distribution of PCG may be associated with different CYP1B1 mutation patterns. Such information may be useful in developing strategies for reliable clinical genetic testing of patients with PCG and their families.     

Compound heterozygous mutations in CYP1B1 gene leads to severe primary congenital glaucoma phenotype

AIM: To identify the novel mutation alleles in the CYP1B1 gene of primary congenital glaucoma (PCG) patients at Shandong Province of China, and investigate their correlation with glaucomatous features. METHODS: The DNA from the peripheral blood of 13 congenital glaucoma patients and 50 ethnically matched healthy controls from the affiliated hospital of Qingdao University were extracted. The coding region of the CYP1B1 gene was amplified by PCR and direct DNA sequencing was performed. Disease causing-variants were analyzed by comparing the sequences and the structures of wild type and mutant CYP1B1 proteins by PyMOL software. RESULTS: Two missense mutations, including A330F caused by c.988G>T&c.989C>T, and R390H caused by c.1169G>A, were identified in one of the 13 PCG patients analyzed in our study. A330F mutation was observed to be novel in the Chinese Han population, which dramatically altered the protein structure of CYP1B1 gene, including the changes in the ligand-binding pocket. Furthermore, R390H mutation caused the changes in heme-protein binding site of this gene. In addition, the clinical phenotype displayed by PCG patient with these mutations was more pronounced than other PCG patients without these mutations. Multiple surgeries and combined drug treatment were not effective in reducing the elevated intraocular pressure in this patient. CONCLUSION: A novel A330F mutation is identified in the CYP1B1 gene of Chinese PCG patient. Moreover, in combination with other mutation R390H, this PCG patient shows significant difference in the CYP1B1 protein structure, which may specifically contribute to severe glaucomatous phenotype.     

Two novel variants in CYP1B1 gene: a major contributor of autosomal recessive primary congenital glaucoma with allelic heterogeneity in Pakistani patients

AIM: To find the CYP1B1 mutations associated with primary congenital glaucoma (PCG) in Pakistani consanguineous pedigrees. METHODS: After getting informed consent, 11 consanguineous pedigrees belonging to different ethnic groups were enrolled. Detailed medical history was recorded and pedigrees were drawn. The standard ophthalmological examination was done to characterize the phenotype. Genomic DNA was extracted from 10 mL whole blood and coding exons and exon intron boundaries of CYP1B1 gene were directly sequenced. Bioinformatics tools were used to model the mutant protein and predict the effect of novel variants on protein structure and function. RESULTS: Sequencing analysis revealed 5 different CYP1B1 variants in 7 families (7/11; 64%), including two novel variants. A common mutation, p.R390H was found in four families, whereas p.P437L was found once in a family. Two novel variants, a homozygous non sense variant p.L13* and a compound heterozygous variant, p.P350T along with p.V364M were segregating with PCG in two families. All the patients had the variable onset and severity of the disease. The success rate of early clinical interventions was observed dependent on mutation types and position. Two different haplotypes were associated with frequently found mutation, p.R390H. CONCLUSION: Identification of novel CYP1B1 variants reassert the genetic heterogeneity of Pakistani PCG patients. The patients with missense mutations show severe phenotypic presentations and poor vision after surgical interventions as compare to patients with null variants. This may help to better understand the role of CYP1B1 mutations in the development of PCG and its course of pathogenicity.     

华南地区与西南地区先天性青光眼临床特点的比较

目的通过对中山眼科中心与华西医院眼科中心收治的原发性先天性青光眼患者进行对比,探讨我国华南、西南地区先天性青光眼发病的异同性。方法以华西医院眼科中心（WCHOC）报道的原发性先天性青光眼的研究结果为参照,与中山眼科中心（ZOC）在同一时段（2002年1月至2004年12月）收治的原发性先天性青光眼患者进行回顾性对比分析。结果ZOC入组的原发性先天性青光眼患者有51例（102眼）,WCHOC患者40例（80眼）。两组患者均以男性为多,分别为3.25：1和2.07：1;双眼发病为主：家族史均不明显;发现年龄在两地患者中无显著性差异（P〉0.01）：但WCHOC患者就诊年龄远远大于ZOC患者（分别为36个月与9个月）;就诊时已有视功能严重损害者以WCHOC患者为多：手术治疗均以小梁切开联合小梁切除术为主。结论与中山眼科中心原发性先天性青光眼患者比较,华西眼科中心患者就诊较晚,视功能损害严重,诊断、治疗相对滞后。在一定程度上可能与地区经济水平对该病诊治的影响有关。中国先天性青光眼的防治工作仍存在很大的不平衡性,值得关注。