运用构象敏感凝胶电泳筛查常染色体显性视网膜色素变性患者视紫红质基因突变的研究  

Mutation screening of the rhodopsin gene in patients with autosomal dominant retinitis pigmentosa with conformation-sensitive gel electrophoresis

作　　者：张晓莉[1] 赵红霞[2] 孟晓红[3] 张雪[1] 黄军富[1] 

机构地区：[1]解放军第三军医大学西南医院基因诊断治疗中心,重庆市400038 [2]云南省红十字会医院眼科,云南省昆明市650021 [3]解放军第三军医大学西南医院眼科,重庆市400038

出　　处：《中国临床康复》2005年第10期100-101,共2页Chinese Journal of Clinical Rehabilitation

摘　　要：目的:视网膜色素变性(retinitispigmentosa,RP)是一组最常见的遗传性致盲眼底病。突变研究至今已证实视紫红质(rhodopsin,RHO)基因突变可导致常染色体显性遗传RP(autosomaldominantRP,ADRP),并且可能是目前ADRP最常见的病因。对27例ADRP先证者进行RHO基因突变的筛选与检测,以探明中国ADRP患者基因突变的特征和意义。方法:1999～2002年在解放军第三军医大学西南医院收集到27例ADRP家系。患者经过全面的眼科检查(包括眼底镜观察及视网膜电图测试),RP诊断的确立依照国内外的通用标准。在27例ADRP先证者中运用构象敏感凝胶电泳(conformationsensitivegelelectrophoresis,CS-GE)和DNA直接测序方法检测RHO基因全编码区范围内的点突变。结果:一个ADRP家系的4名患者在第347密码子发生单碱基置换突变,Pro347Leu;另一个ADRP家系中一名晚发型患者及其目前还未出现明显症状的女儿在第327密码子出现缺失突变,Pro327(1-bpdel),而对照组100例健康成年人未发现上述两种突变。结论:27例ADRP先证者中检出2例携带RHO基因突变,由此RHO基因在这组ADRP患者中的突变频率约为7.4%(2/27)。Pro347Leu突变改变了视蛋白C末端一段高度保守的氨基酸序列,可能使该蛋白在胞内的运输发生障碍。Pro327(1-bpdel)使突变蛋白的羧基末端失去了?AIM:Retinitis pigmentosa(RP) is the most common inherited fundus oculi diseases that can cause blindness.From the studies on mutation,it has been confirmed that mutation of rhodopsin(RHO) usually is the cause of autosomal dominant retinitis pigmentosa(ADRP),and may be the most common one.The present study aimed to explore the character and significance of gene mutation in Chinese patients with ADRP through selecring and detecting the RHO mutation in 27 ADRP proposita .METHODS:From 1999 to 2002,27 cases of ADRP families were collected from Southwest Hospital,Third Military Medical University of Chinese PLA.All of the patients received overall ophthalmological examination including funduscope observation and electroretimogram detection.The diagnosis of retinitis pigmentosa(RP) was established according to the common criteria home and abroad.The exons and splice sites in the total coding region of RHO gene in the 27 cases of ADRP were detected by using conformation sensitive gel electrophoresis(CSGE) and direct DNA sequencing.RESULTS:Two RHO mutations,Pro347Leu,single base substitution mutation at the 347th codon,was found in 4 patients of one ADRP family,and Pro327(1 bp del),loss mutation at the 327th condon,was found in 1 late episode patient of another ADRP family whose daughter was not found obvious symptoms at the 327th condon.However,the above two mutations were not found in the 100 healthy adults as controls.CONCLUSION:Two of the 27 ADRP patients were detected with RHO mutations,so the frequency of RHO mutations among the ADRP families is about 7.4% (2/27).A highly conserved C terminal sequence QVS(A)PA was altered due to Pro347Leu and thereby resulting in an intracellular transmission disturbance in this protein.Loss of all phosphorylation sites at the C terminus and the highly conserved sequence QVS(A)PA may occur because of Pro327(1 bp del).To elucidate the possible pathogenic mechanism of such mutant,transgenic models and the system for transfected cell culture will be established.

关 键 词：染色体 人 遗传学 视网膜炎 色素性 突变 

分 类 号：R774.1[医药卫生—眼科]