摘要
目的 评估全外显子测序在儿童神经发育障碍中的诊断价值.方法 方法学评价.对2015年12月至2016年12月间首都儿科研究所附属儿童医院门诊和病房收治的35例不明原因神经发育障碍患儿,收集患儿临床资料,运用全外显子测序技术进行检测,完成遗传病因诊断.利用多种生物信息学软件分析测序数据,结合患儿的表型寻找潜在致病基因/基因组变异,根据美国医学遗传学与基因组学学会的基因变异解读指南完成变异致病性评估,同时利用Sanger测序、Real-time PCR、MLPA方法完成患者验证及家系成员的分离分析.结果 35例不明原因的神经发育障碍患儿中,检测出致病性单核苷酸变异（SNVs）14个、致病性基因组拷贝数变异（CNVs）3个,检出率为48.6%.14例致病性SNVs中,11例是OMIM中有明确致病基因的综合征（如CHARGE 综合征、Wiedemann-Steiner综合征、Cockayne综合征等）,其中新生变异共6个,占54.6%（6/11）.利用全外显子测序数据筛选出了3个致病性CNVs,包括2个微重复和1个微缺失.同时,还发现一例携带MECP2移码变异的女性患儿,其父亲精子DNA携带该位点的低频细胞嵌合体变异,变异频率为8.4%.结论 全外显子测序对儿童神经发育障碍的病因诊断率可达48.6%,全外显子测序数据除了检测出致病性/可能致病性的SNVs,还可以筛选出致病性CNVs,从而有效提高疾病诊断率.
Objective To evaluate the application value of whole exome sequencing （WES） in diagnosis of NDDs （neuro-developmental disorders） children.Metheod WES was used for the diagnosis of 35 unexplained NDD children, which admitted to the outpatient and ward of Children′s hospital affiliated to Capital institute of pediatric from November 2015 to November 2016.These children′s clinical data was collected detailedly.Using bioinformatics software tools combining with patient′s phenotype, the candidate genetic/genomic variants of these patients were identified from WES data.The final pathogenicity of genetic/genomic variants was interpreted according to the guideline of the American College of Medical Genetics and Genomics （ACMG）, meanwhile, the variants validation and co-separation analysis in the parents and their family members were performed by Sanger sequencing, real time-PCR and multiplex ligation-dependent probe amplification （MLPA）.Results 14 pathogenic single nucleotide variants （SNVs） and three pathogenic copy number variations （CNVs） were detected in the 35 NDD children, the detection rate in this study is 48.6%.Among the 14 pathogenic SNVs, 11 of them are the definite NDD-related genes according to OMIM database （such as CHARGE syndrome, Wiedemann-Steiner syndrome, Cockayne syndrome, etc.）, and six of them are de novo （6/11, 54.6%）.Three pathogenic CNVs were identified from WES data, including two microduplications and one microdeletion.Meanwhile, a female child carrying a frame shift mutation in MECP2 was found and the germline mosaicism with low-frequency mutation of this site （8.4%） was confirmed by his father＆#39;s sperm.Conclusions The diagnosis rate of WES in NDDs children is 48.6% in our small-sample study.In addition to pathogenic/likely pathogenic SNVs, CNVs can be detected successfully from WES data, which effectively improved the diagnosis yield in NDDs children.
出处
《中华检验医学杂志》
CAS
CSCD
北大核心
2017年第8期623-629,共7页
Chinese Journal of Laboratory Medicine
基金
国家自然科学基金项目（31671310,81401207）
北京市自然科学基金面上项目（7162029）
首都卫生发展科研专项（2014-2-1131）
北京市科技新星计划交叉学科合作课题项目（xxje201717）
北京市百千万人才工程创新研发类项目
北京市卫生系统215高层次人才项目
中国医学科学院医学与健康科技创新工程（CAMS-12M）
关键词
发育障碍
外显子组
多态性
单核苷酸
DNA拷贝数变异
序列分析,DNA
Developmental disabilites
Exome
Sequence analysis,DNA
Polymorphism,single nucleotide
DNA copy number variations
