圆锥角膜家系中ZEB1基因突变的致病性分析  

Mutation analysis of ZEB1 in a pedigree with keratoconus

作　　者：赵良慧 蔡涛 杜显丽[2] ZHAO Lianghui;CAI Tao;DU Xianli(School of Clinical Medicine,Weifang Medical University,Weifang261053,Shandong,China;Department of Optometry and Contact Lens,Qingdao Eye Hospital of Shandong First Medical University/Shandong Eye Institute/Shandong Provincial Key Laboratory of Ophthalmology-National Key Laboratory Cultivation Base,Qingdao266071,Shandong,China)

机构地区：[1]潍坊医学院临床医学院,山东潍坊261053 [2]山东第一医科大学附属青岛眼科医院视光学与接触镜科/山东省眼科研究所/山东省眼科学重点实验室-省部共建国家重点实验室培育基地,山东青岛266071

出　　处：《山东大学耳鼻喉眼学报》2021年第2期98-104,共7页Journal of Otolaryngology and Ophthalmology of Shandong University

基　　金：青岛市民生科技计划项目(19-6-1-24-nsh)。

摘　　要：目的分析圆锥角膜男性患者的临床表型及致病基因突变,寻找致病基因突变位点,探讨表型与基因型之间的关系。方法收集1例圆锥角膜男性患者及其父母的临床资料,完善其眼科检查,用Pentacam角膜地形图及生物力学分析提高疾病诊断。提取该家系中全部成员的外周血基因组DNA,选取先证者进行全外显子组测序,最终通过家系内共分离验证致病突变,进一步分析该突变与患者表型间的关系。结果患者被诊断为圆锥角膜初发期,其父亲被诊断为圆锥角膜完成期。全外显子组测序发现先证者的锌指转录因子(ZEB1)基因c.643G>C突变,该突变导致了ZEB1基因所编码蛋白第215位氨基酸由缬氨酸变为亮氨酸(p.V215L)。保守性分析显示该突变在各物种中高度保守,生物信息学预测结果表明该突变具有较高的致病性。该基因的突变亦存在于其父亲基因中。先证者的母亲临床表现正常,该突变在先证者的母亲和100个不相关的正常对照中不存在。结论临床检查结果表明该家系内先证者及其父亲均符合典型的圆锥角膜表型,全外显子组测序发现了ZEB1基因上一个错义突变(c.643G>C),该突变在家系内共分离。Objective To analyze the clinical phenotype of and pathogenic gene mutation in a male child with keratoconus, to identify the mutation site of the pathogenic gene, and to discuss the relationship between genotype and phenotype. Methods Clinical data of a male child with keratoconus and his parents were collected. Pentacam corneal topography, Belin/Ambrosio Enhanced Ectasia Display, and biomechanical analysis were used to improve the diagnosis of keratoconus. Peripheral blood genomic DNA of the family members was obtained, and the exome of the proband was sequenced using whole exome sequencing technology. Finally, the pathogenic mutation was found to be co-segregated within the family, and the relationship between the mutation and patient phenotype was further analyzed. Results The proband and his father were both diagnosed with keratoconus. Whole exome sequencing revealed a mutation(c.643 G>C) in the zinc finger E-box-binding homeobox 1(ZEB1) gene that led to replacement of valine at 215 position in the protein encoded by ZEB1 with leucine(p.V215 L). Conservative analysis showed that this mutation is highly conserved in various species. Bioinformatics predictions showed that the mutation is highly pathogenic. Mutations in the gene were also present in the paternal gene. The mother of the proband presented with normal clinical manifestations, and the mutation was not detected in the genetic tests of the mother and 100 unrelated normal controls. Conclusions The clinical phenotypes of both proband and his father were consistent with the typical keratoconus phenotype. Exon sequencing revealed a new mutation in the ZEB1 gene(c.643 G>C, p.V215 L). The mutation was co-segregated within the family.

关 键 词：圆锥角膜 全外显子组测序 ZEB1 生物力学分析 Pentacam眼前节分析系统 

分 类 号：R765.21[医药卫生—耳鼻咽喉科]