1例妊娠中期三倍体胎儿的产前诊断

Prenatal diagnosis of a triploid fetus in the second trimester

目的利用不同检测方法对1例孕中期三倍体胎儿进行产前诊断,探讨三倍体的形成原因及各检测方法的优缺点。方法采集胎儿羊水,利用羊水细胞培养技术进行染色体核型分析,同时利用拷贝数变异检测(copy number variation sequencing,CNV-seq)和染色体微阵列分析(chromosome microarray analysis,CMA)技术分别进行全基因组拷贝数变异检测和染色体倍数检测。结果胎儿羊水细胞染色体核型分析结果为68,XX。CNV-seq检测结果显示46,XN(70%)和46,X,+10(30%)嵌合。CMA检测结果显示为arr[hg19](1-22)×3,(XX)×1(60%)和arr[hg19](1-22)×3,(X)×1,+10(40%)的嵌合。结论CMA检测不仅能够进行全基因组拷贝数变异检测,而且也可进行染色体数目异常和单亲二倍体的检测,相比CNV-seq更适用于产前遗传病检测。

Objective To use different detection methods to conduct prenatal diagnosis of a triploid fetus in the second trimester of pregnancy,to explore the causes of triploidy and the advantages and disadvantages of each detection method.Methods Collect fetal amniotic fluid,use amniotic fluid cell culture technology for chromosome karyotype analysis,at the same time use copy number variation sequencing(CNV-seq)and chromosome microarray analysis(CMA)technology to perform genome-wide copy number variation detection and chromosome multiple detection.Results The karyotype analysis result of fetal amniotic fluid cells was 68,XX.The CNV-seq test results showed 46,XN(70%)and 46,X,+10(30%)chimerism.CMA test results showed as mosaic of arr[hg19](1-22)×3,(XX)×1(60%)and arr[hg19](1-22)×3,(X)×1,+10(40%).Conclusion The CMA test can not only detect the copy number variation of the whole genome,but also detect the abnormal number of chromosomes and uniparental diploidy.Compared with CNV-seq,it is more suitable for the detection of prenatal genetic diseases.