摘要
背景 先天性白内障是儿童致盲的重要原因,多数先天性白内障与遗传有关.目前已知的与常染色体显性遗传先天性白内障（ADCC）有关的基因有39个. 目的 采用全外显子组测序法对一ADCC家系的致病突变基因进行筛查和分析.方法 纳入2014年8月-9月在郑州大学第一附属医院就诊的一ADCC家系,分别采集家系中14例患者和14名表型正常成员外周静脉血各10 ml,同期同法采集100名健康体检者10 ml的外周静脉血作为对照.用标准酚-氯仿提取法提取所有受检者基因组DNA,并采用全外显子组测序法将先证者的DNA进行全外显子组测序,与数据库对比后筛选出候选基因突变位点,设计突变基因位点引物后采用PCR技术对家系中受检者及100名健康对照者的该基因位点进行扩增并测序,以验证候选基因的致病性并分析其致病机制.结果 该家系共5代68名成员,患病者20例,遗传方式符合常染色体显性遗传方式.患者均双眼发病,晶状体混浊以皮质性为主.先证者全外显子组测序后分析发现,13号染色体GJA3基因的2号外显子第143位核糖核苷酸A突变为G（c.143A＞G）,导致其编码的第48位氨基酸由谷氨酸变为甘氨酸（p.E48G）.PCR扩增产物测序结果显示该家系中患病受检者DNA均有此突变,但该家系中表型正常的受检者及100名健康对照者该候选基因均不存在此突变.结论 GJA3基因c.143A＞G为该ADCC家系的致病基因突变位点,增补了GJA3基因的突变谱.
Congenital cataract is one of the important reasons for the blindness of children,and most congenital cataracts are genetic.At present,thirty-nine genes have been identified relating to autosomal dominant congenital cataract （ADCC）.Objective This study was to identify and analyze the virulence gene of a Chinese family pedigree with ADCC by whole-exome sequencing.Methods A Chinese ADCC family was recruited in Affiliated First Hospital of Zhengzhou University from August to September in 2014.The family disease history and clinical data were recorded.The peripheral venous blood of 10 ml was collected in 14 patients with congenital cataract and 14 families with normal phenotype,and the peripheral blood samples were obtained from 100 healthy examined people as controls.The genomic DNA was extracted form all subjects using standard phenol chlorum method,and proband DNA was screened by whole-exome sequencing.Then mutation locus of the candidate gene was selected after compared with the information of database in the proband.The mutation locus of the candidate gene from 14 normal families and 100 healthy controls were amplified and sequenced by PCR technique based on the primer sequence of mutation locus of proband to verify the pathogenic gene of this ADCC family.This study protocol was approved by Ethic Committee of Affiliated First Hospital of Zhengzhou University and complied with Helsinki Declaration.Written informed consent was obtained from subjects or custodian before any medical examination.Results The family had a total of 5 generations of 68 members,in which 20 subjects were found with congenital cataract.The inheritance mode consisted with autosomal dominant inheritance.Cortical cataract was found in both eyes in the patients.Whole-exome sequencing showed that the 143rd ribonucleotide A of exon 2 explicit factor of chromosome 13 GJA3 gene mutated into G （c.143A〉G） in the proband,which resulted in the 48th amino acids changed from glutamate into glycine （p.E48G）.PCR amplification product sequencing displayed that the same mutation of DNA appeared in all the patients of this family,while not the same mutation was seen in the candidate genes of normal phenotype families and 100 healthy controls.Conclusions GJA3 gene c.143A〉G is a virulence mutation site in this ADCC family,it is a supplement of the mutation spectrum of GJA3 gene.
出处
《中华实验眼科杂志》
CAS
CSCD
北大核心
2016年第10期916-919,共4页
Chinese Journal Of Experimental Ophthalmology
