基因组拷贝数变异测序与染色体核型分析在胎儿遗传学诊断中的比较

目的 比较基因组拷贝数变异测序(CNV-seq)技术和染色体核型分析和在产前胎儿遗传学诊断中的应用价值.方法 收集来我院有产前诊断指征进行羊水穿刺的259例孕妇,取材后,送检染色体核型分析和CNV-seq,比较两种方法在产前诊断中的优缺点.结果 259例标本中,共诊断异常染色体核型及微缺失微重复23例,总阳性诊断率8....     

罕见特纳综合征的细胞遗传学和分子遗传学检测一例

特纳综合征是较常见的性染色体异常疾病。本文报道了1例罕见性染色体数目和结构异常的特纳综合征,并利用荧光原位杂交(FISH)、全基因组低深度测序(CNV-seq)等遗传学技术明确了结构异常染色体的性质,为临床医生和遗传分析人员提供诊断思路。     

高通量测序技术在产前诊断中的应用

拷贝数变异测序（CNV-seq）、基因包检测、全外显子组测序（WES）等高通量测序技术已用于产前诊断，几种技术各有优势和不足。国内外相继制定了拷贝数变异（CNV）解读指南、WES应用等指南。结合实践经验，文章讨论了如何在产前诊断中合理应用几种技术，期待将来全基因组测序（WGS）也可用于产前诊断。     

CNV-seq技术检测90例发育迟缓患儿基因组拷贝数变异的遗传学分析

目的 探讨发育障碍疾病患儿致病性拷贝数变异(CNV)的特征.方法 收集2017至2019年诊断为发育迟缓、并经核型分析患儿的临床资料,采集患儿外周血进行基于高通量测序的低深度全基因组测序(CNV-seq).利用ClinVar、DECIPHER、OMIM、DGV数据库注释CNV数据,依据ACMG评估CNV致病性,并通过P...     

产前B超、MRI及高通量测序在先天性肾缺如中的应用

肾缺如是一种罕见的先天性出生缺陷,单肾缺如发病率约为1‰,双肾缺如发病率为0.1‰~0.3‰,遗传是其主要致病因素,但其发病机制尚不明确。临床上,大多数肾缺如胎儿并不具有典型的体征和症状,同时也缺乏高特异性的诊断指标。目前,肾缺如的胎儿往往是孕妇在孕中晚期产检时,通过产前B超检查被发现,少数孕妇会选择进一步完善MRI进行确诊。因此,临床实践中肾缺如的产前诊断具有明显的局限性。近年来,随着高通量测序技术的发展,拷贝数变异测序和全外显子测序等技术逐渐被广泛运用于妇产与遗传学科领域。高通量测序技术用于胎儿产前诊断,具备母胎安全性高、准确性高、操作简便等优势,不仅为肾缺如的产前诊断方式提供了新的选择,也为探索其遗传病因及相关机制提供了科学依据。本文将就正常胚胎肾脏发育以及产前B超、MRI、拷贝数变异测序和全外显子测序等相关产前诊断技术在肾缺如中的应用进行综述。     

Molecular delineation of de novo small supernumerary marker chromosomes in prenatal diagnosis,a retrospective study

ObjectivesTo define the genotype-phenotype correlation of small supernumerary marker chromosomes (sSMCs) and conduct precise genetic counseling, we retrospectively searched and reviewed de novo sSMCs cases detected during prenatal diagnosis at The First Affiliated Hospital of Zhengzhou University.Materials and methodsChromosome karyotypes of 20,314 cases of amniotic fluid from pregnant women were performed. For 16 samples with de novo sSMCs, 10 were subjected to single-nucleotide polymorphism (SNP) array or low-coverage massively parallel copy number variation sequencing (CNV-seq) analysis.ResultsAmong the 10 sSMCs cases, two sSMCs derived from chromosome 9, and three sSMCs derived from chromosomes 12, 18 and 22. The remaining 5 cases were not identified by SNP array or CNV-seq because they lacked euchromatin or had a low proportion of mosaicism. Four of them with a karyotype of 47,XN,+mar presented normal molecular cytogenetic results (seq[hg19] 46,XN), and the remaining patient with a karyotype of 46,XN,+mar presented with Turner syndrome (seq[hg19] 45,X). Five sSMCs samples were mosaics of all 16 cases.ConclusionConsidering the variable origins of sSMCs, further genetic testing of sSMCs should be performed by SNP array or CNV-seq. Detailed molecular characterization would allow precise genetic counseling for prenatal diagnosis.