350例超声异常胎儿的染色体及全基因组拷贝数变异分析

目的 探讨胎儿超声异常与胎儿染色体核型及全基因组拷贝数变异(CNVs)的相关性。方法 选择2017年7月—2019年6月在哈尔滨医科大学附属第二医院产前诊断中心就诊并自愿行羊水穿刺的孕妇为研究对象，对其中350例超声提示胎儿异常的孕妇进行常规染色体核型分析高通量测序CNVs检测，比较不同超声异常指标所对应的染色体异常核型及致病性CNVs的检出率。孕妇年龄18～45岁，孕周17～27周。结果 350例超声异常中，软指标异常243例，占69.4%,其中染色体核型异常49例，检出率20.2%;致病性CNVs 54例，检出率22.2%;超声结构异常107例，占30.6%,其中染色体核型异常29例，检出率27.1%;致病性CNVs 33例，检出率30.8%。其中有17例超声异常的胎儿染色体核型正常，而CNVs提示有致病性变异，占4.9%。结论 在胎儿超声异常行产前诊断时，联合染色体核型分析和高通量测序CNVs检测有利于提高检出率，降低出生缺陷的发生风险。

Analysis of the chromosomal and whole genome copy number variations in 350 fetuses with ultrasound abnormality

Objective To investigate the correlation of karyotype and pathogenic copy number variations(CNVs)with fetal ultrasound abnormalities.MethodsParticipants were pregnant women who visited to Prenatal Diagnosis Center of the Second Affiliated Hospital of Harbin Medical University from July 2017 to June 2019 and volunteered to have amniocentesis test.350 cases of pregnant women with fetal abnormality indicated by ultrasound were included in our study and the detection rate of abnormal karyotypes and pathogenic CNVs corresponding with different ultrasound indicators were compared.Participants included in the study were between 18 and 45 years old with gestational age between 17 and 27 weeks.ResultsAmong the 350 cases with ultrasound abnormality,243 cases(69.4%)had abnormal ultrasound soft markers,of which 49 were chromosomal karyotype abnormality(20.2%),54 had pathogenic CNVs(22.2%);107 cases of the 350 cases were ultrasound structural abnormality(30.6%),29 of which were chromosomal karyotype abnormality(27.1%),33 of which had pathogenic CNVs(30.8%);Among the 350 cases,17 cases had normal karyotype,while CNVs showed pathogenic variation,accounting for 4.9%.ConclusionIn prenatal diagnosis of fetal ultrasound abnormalities,the combination of chromosomal karyotype analysis and high-throughput sequencing CNVs detection can improve the detection rate and reduce the risk for birth defect.