超声心动图提示异常的胎儿的产前遗传学诊断

Prenatal genetic diagnosis of fetuses with anomalies revealed by fetal echocardiography

目的:对超声心动图提示异常的胎儿进行羊水细胞核型分析和染色体微阵列分析(chromosomal microarray analysis,CMA),探讨胎儿心脏异常与染色体异常的相关性。方法:收集整理2019年1月至2021年12月的205例胎儿的超声检查结果,其中97例具有心脏相关的软指标异常,108例具有心脏结构异常。138例仅具有超声心动图异常,38例合并心外软指标异常,29例合并心外结构畸形。结果:心脏相关软指标异常组与心脏结构异常组遗传学异常的检出率无显著差异(P>0.05)。与仅有超声心动图异常组相比,合并心外软指标异常组、合并心外结构畸形组染色体非整倍体的检出率显著偏高(P<0.05)。羊水细胞核型分析共检出28例染色体非整倍体(其中1例为特殊嵌合体),2例平衡易位,1例额外小标记染色体。CMA共检出27例染色体非整倍体,19例染色体拷贝数变异(copy number variation,CNV),1例单亲源二体。结论:产前诊断应高度重视胎儿心脏相关软指标的提示作用,合并心外软指标异常或心外结构畸形的病例非整倍体发病率较高。染色体核型分析对于检测平衡易位及特殊嵌合体具有明显的优势,而CMA有助于检出CNV。通过明确其遗传学病因,可为产前遗传咨询提供依据。

Objective To carry out amniocyte karyotyping analysis and chromosomal microarray analysis(CMA)for women with anomalies revealed by fetal echocardiography.Methods From January 2019 to December 2021,genetic testing was carried out for 205 fetuses including 97 with soft marker anomalies and 108 with structural heart abnormalities.Among these,138 only had abnormal fetal echocardiography,whilst 38 and 29 were complicated with extracardiac soft marker anomalies and extracardiac structural malformation,respectively.Results No significant difference was detected in the detection rate of genetic anomalies between fetuses with heart-related soft markers and those with abnormal heart structures(P>0.05).Compared with those with abnormal fetal echocardiography alone,the detection rates of chromosomal aneuploidies in those with abnormal extracardiac soft markers or abnormal extracardiac structures were significantly higher(P<0.05).Twenty-eight chromosomal aneuploidies(including a rare mosaicism),2 balanced translocations and 1 supernumerary marker chromosome were detected by karyotyping analysis.Twenty-seven aneuploidies,19 copy number variations(CNVs)and 1 uniparental disomy were detected by CMA.Conclusion Prenatal diagnosis has attached great importance to the suggestive role of fetal heart-related soft markers,and chromosomal aneuploidies are more common among fetuses with abnormal extracardiac soft markers and extracardiac structural abnormalities.Chromosomal Karyotyping is useful for the detection of balanced translocations and mosaicisms.CMA is helpful for the detection of CNVs.Identification of the genetic causes can facilitate genetic counseling for the affected couples.