遗传 ›› 2017, Vol. 39 ›› Issue (3): 241-249.doi: 10.16288/j.yczz.16-339

• 研究报告 • 上一篇    下一篇

家族性渗出性玻璃体视网膜病变患者LRP5基因突变研究

刘玉庆1,3, 朱雄1,3, 李姝锦4, 杨业明1,3, 杨牧1,4, 赵培泉2, 朱献军1,3,4   

  1. 1. 电子科技大学医学院,电子科技大学附属医院,四川省人民医院人类疾病基因研究四川省重点实验室,成都 610072;
    2. 上海交通大学医学院附属新华医院眼科学系,上海 200092;
    3. 四川省医学科学院,四川省人民医院实验动物研究所,成都 610212;
    4. 中国科学院成都生物研究所,成都 610042
  • 收稿日期:2016-10-16 修回日期:2017-01-18 出版日期:2017-03-20 发布日期:2017-02-23
  • 通讯作者: 朱献军,研究员,博士生导师,研究方向:疾病基因研究。E-mail: xjzhu@uestc.edu.cn
  • 作者简介:刘玉庆,硕士研究生,专业方向:生物医学工程。E-mail: liuyuqing610@yeah.net,朱雄,博士研究生,专业方向:生物医学工程。E-mail: zhuxiong7555711@163.com,刘玉庆和朱雄为并列第一作者。
  • 基金资助:
    国家自然科学基金项目(编号:81470668, 81271007)和四川省科技厅项目(编号:2014JQ0023, 2016TD0009)资助

Identification of LRP5 mutations in families with familial exudative vitreoretinopathy

Yuqing Liu1,3, Xiong Zhu1,3, Shujin Li4, Yeming Yang1,3, Mu Yang1,4, Peiquan Zhao2, Xianjun Zhu1,3,4   

  1. 1. Sichuan Provincial Key Laboratory for Human Disease Gene Study, Hospital of the University of Electronic Science and Technology of China and Sichuan Provincial People's Hospital, Chengdu 610072, China;
    2. Department of Ophthalmology, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai 200092, China;
    3. Institute of Laboratory Animal Sciences, Sichuan Academy of Medical Sciences and Sichuan Provincial People’s Hospital, Chengdu 610212 China;
    4. Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610042, China
  • Received:2016-10-16 Revised:2017-01-18 Online:2017-03-20 Published:2017-02-23
  • Supported by:
    Supported by the National Natural Science Foundation of China (Nos; 81470668, 81271007) and Sichuan Science and Technology Department project (Nos; 2014JQ0023, 2016TD0009)

摘要: 家族性渗出性玻璃体视网膜病变(familial exudative vitreoretinopathy, FEVR)是一种遗传性眼科疾病,主要特征为视网膜周边血管发育异常和病变。由于病变程度不同,临床表型可从无明显症状到眼睛完全失明。本文通过研究3个中国FEVR家系和1个散发型患者,探索其致病突变与疾病表型之间的关系。收集家系中患者及亲属的外周血制备基因组DNA,设计引物以扩增FEVR致病基因FZD4LRP5NDPTSPAN12的外显子区域并通过Sanger法进行测序。结果发现,在LRP5基因上存在3个未在dbSNP数据库及千人基因组计划数据库中报道过的杂合突变p.M181R、p.R399S和p.G503R,以及2个已发现但未在FEVR中报道过的杂合突变p.R494Q和p.G876S。生物信息学分析表明这5个突变位点均高度保守,为有害突变。荧光素酶报告基因实验证明了这5个突变均不能激活Norrin/β-catenin信号通路,进一步证明了这5个突变的致病性。该研究扩充了我国FEVR疾病的遗传数据库,可为该疾病的分子诊断提供依据。

关键词: 家族性渗出性玻璃体视网膜病变, 低密度脂蛋白受体相关蛋白5, 基因突变

Abstract: Familial exudative vitreoretinopathy (FEVR) is a hereditary eye disease characterized by defects in the development of periphery retinal vessels. However, the clinical phenotypes of FEVR vary widely from asymptomatic to complete blindness. We analyzed patients from three Chinese families and one sporadic patient with FEVR to investigate the clinical features and disease-causing mutations. Ocular phenotypes included increased ramification of the peripheral retinal vessels, a peripheral avascular zone, inferotemporal dragging of the optic disc and macula, and retinal folds. Peripheral blood DNA samples were obtained from patients with FEVR and their family members. Primers were designed to amplify the coding exons and adjacent intronic regions of the FEVR-causing genes FZD4, LRP5, NDP and TSPAN12. By polymerase chain reactions, each amplicon was subjected to direct Sanger sequencing analysis. Potential pathogenic changes of the sequence variants were analyzed by the orthologous protein sequence alignment and computational prediction software. We identified five LRP5 mutations: three novel heterozygous mutations-p.M181R, p.R399S and p.G503R and two known mutations that were never reported in FEVR patients: p.R494Q and p.G876S. All five mutations involved highly conserved residues and were predicted to be damaging by SIFT and PolyPhen-2. None was present in 500 normal individuals. To assess the pathogenesis of these mutations, wild-type and all five mutant LRP5 proteins were assayed for the ability to activate the Norrin/β-catenin pathway by established luciferase reporter assays, and all mutants failed to activate the pathway. This study extends the genetic database of the FEVR disease in China and provides a basis for molecular diagnosis of the disease.

Key words: familial exudative vitreoretinopathy (FEVR), low density lipoprotein receptor related protein-5 (LRP5), gene mutation