摘要
目的明确1例不明原因生长发育迟缓患儿染色体异常的性质及来源,分析其与表型的相关性。方法选择2023年7月9日就诊于深圳市龙华区妇幼保健院神经康复科的1例患儿作为研究对象。用全外显子组测序(WES)技术对患儿进行检测,用G显带染色体核型分析对患儿及其父母进行检测,追溯患儿母亲孕期无创产前检测(NIPT)测序数据进行比对。结果WES未检测到与临床相关的单基因明确致病性变异,拷贝数变异(CNV)分析提示患儿染色体18q22.1q23区存在14.31 Mb缺失,具体为seq[GRCh37]del(18)(q22.1q23);chr18:g.63704349-78016748del。G显带核型分析示患儿染色体核型为:46,XX,del(18)(q22.1q23),其父母核型均未见异常。追溯母亲孕期NIPT测序数据,胎儿18号染色体q22.1q23区域的Z值有较大偏移,考虑为片段缺失。结论患儿为罕见的18q末端部分缺失,其基因型与表型的相关性有助于临床诊疗及遗传咨询。
Objective To define the nature and origin of a chromosomal aberration in a child with unexplained growth and development retardation,and to analyze its genotypeGphenotype correlation.Methods A child who was admitted at the Department of Neurological Rehabilition of Maternal and Child Health Care Hospital of Longhua District,Shenzhen on July 9,2023 was selected as the study subject.Applying whole exome sequencing(WES)to analyze the child,and chromosomal karyotypes of the child and her parents were determined with routine G banding analysis.Traceability of non-invasive prenatal testing(NIPT)sequencing data from the mother during pregnancy was done for comparison.Results Clinically relevant pathogenic variants in monogenic disease susceptibility genes are not detected in patient with WES.Copy number variation(CNV)analysis revealed a 14.31 Mb deletion in the 18q22.1q23 region of the chromosome in the child,specifically seq[GRCh37]del(18)(q22.1q23);Chr18:g.63704349-7801648del.Karyotyping analysis suggested that the chromosomal karyotype of the child was 46,XX,del(18)(q22.1q23),whilst no karyotypic abnormality was found in either of his parents.By tracing NIPT sequencing data from the mother during pregnancy,there is a significant deviation in the Z value of the q22.1q23region of fetal chromosome 18,which is considered a fragment deletion.Conclusion 18q partial deletion carried by the child was confirmed.WES can clarify the CNV origin of chromosomal aberrations.Analysis of the correlation between genotype and phenotype can facilitate the clinical diagnosis and genetic counseling.
作者
裘娟
卢建
叶夏
余艳红
张谞卓
卢静钿
李宏
欧阳秋星
QIU Juan;LU Jian;YE Xia;YU Yanhong;ZHANG Xuzhuo;LU Jingtian;LI Hong;OUYANG Qiuxing(Center of Prenatal Diagnosis,Maternal and Child Health Care Hospital of Longhua District,Shenzhen,Shenzhen,Guangdong 518109,China;Center of Medical Genetics,Maternal and Child Health Care Hospital of Guangdong Province,Guangzhou,Guangdong 511442,China;Department of Neurological Rehabilition,Maternal and Child Health Care Hospital of Longhua District,Shenzhen,Shenzhen,Guangdong 518109,China)
出处
《中国优生与遗传杂志》
2024年第4期780-785,共6页
Chinese Journal of Birth Health & Heredity
基金
广东省医学科研基金(B2023412)。
