19号染色体长臂部分重复致癫痫伴发育落后1例遗传及表型分析

Genetic and phenotypic analysis of a case of epilepsy with developmental retardation caused by partial duplication of long arm of chromosome 19

目的探讨1例癫痫伴运动发育落后的患儿的遗传学病因,为临床诊断和遗传咨询提供依据。方法收集2020年1月因癫痫伴运动发育落后到河南省人民医院就诊的1例患儿及其父母外周血各2 mL,采用常规G显带分析患儿及其父母的外周血染色体核型,采用微阵列比较基因组杂交(aCGH)技术对患儿及其父母进行染色体片段重复/缺失进行分析。结果患儿G显带核型分析为46,XX,add(19)(p13.3→qter);aCGH分析显示chr19:49593920_59092570重复,位于q13.33q13.43区域,长度为9.50 Mb;该区域包含基因471个;患儿父母染色体核型分析及aCGH分析结果均未见异常。通过与既往报道该区域重复病例相比较,本例患儿临床表型基本符合19q13.3区重复特征。结论本例19q13.3重复为新发突变,是患儿癫痫伴运动发育落后的原因。传统的G显带联合aCGH技术有利于确诊儿童发育迟缓病因。

Objective To investigate the genetic etiology of a child with epilepsy accompanied by motor retardation.Methods A patient with epilepsy and motor retardation in Henan Provincial People′s Hospital in January 2020 and his parents′peripheral blood 2 mL were collected.G-banded karyotyping and array-based comparative genomic hybridization(aCGH)were used to analyze the duplication/deletion of chromosome segments in child and her pa-rents.Results The karyotype of the patient revealed 46,XX,and add(19)(p13.3→qter),whereas aCGH detected a 9.50 Mb duplication at 19q13.33q13.43[arr(hg19)(49593920_59092570)×3].This region contains 471 genes.No abnormality was discovered in the karyotyping and aCGH analysis of the patient′s parents.The phenotypes of the patient conformed to the previously reported clinical characteristics of 19q13.3 duplication.Conclusions The de novo 19q13.3 duplication is the cause of epilepsy and motor development retardation for the patient.Combined with aCGH,the traditional G banding is valuable to diagnose the patient with developmental delay.