Wu Xiaoqing, Huang Hailong, Chen Xuemei, Chen Xiaolan, Shen Qingmei, He Deqin, Xu Liangpu
Fujian Provincial Key Laboratory for Prenatal Diagnosis and Birth Defect, Fujian Provincial Maternity and Child Health Cave Hospital, the Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350001, China.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi. 2021 Apr 10;38(4):335-338. doi: 10.3760/cma.j.cn511374-20200803-00574.
To assess the impact of confined placental mosaicism (CPM) on non-invasive prenatal testing (NIPT) and pregnancy outcomes.
Copy number variation sequencing (CNV-seq) and single nucleotide polymorphism array (SNP-array) were carried out on placental specimen sampled from eight pregnancies with confirmed false-positive NIPT results. The impact of CPM on NIPT and pregnancy outcomes were analyzed based on the laboratory tests and clinical characteristics.
Five of the eight cases with false-positive NIPT results were proven to be CPM involving trisomy 9, 13, 21, 22, and X, respectively. The mosaic ratios for different placental regions have varied from 4% to 80%. Two fetuses with confirmed CPM showed fetal growth restriction (FGR) and additional ultrasound abnormalities, 1 fetus showed only FGR. The remaining two fetuses showed normal growth.
NIPT is highly sensitive to CPM, whilst CPM is an important cause for false-positive NIPT result. CPM may be associated with FGR. Investigation of the presence of CPM is important for both pre- and post-test genetic counseling and management of the pregnancy.
评估局限性胎盘嵌合体（CPM）对无创产前检测（NIPT）及妊娠结局的影响。
对8例NIPT结果为确诊假阳性妊娠的胎盘标本进行拷贝数变异测序（CNV-seq）和单核苷酸多态性阵列分析（SNP-array）。基于实验室检测及临床特征分析CPM对NIPT及妊娠结局的影响。
8例假阳性NIPT结果病例中，5例被证实为CPM，分别涉及9、13、21、22三体及X染色体异常。不同胎盘区域的嵌合比例在4%至80%之间。2例确诊为CPM的胎儿出现胎儿生长受限（FGR）及其他超声异常，1例仅表现为FGR。其余2例胎儿生长正常。
NIPT对CPM高度敏感，CPM是NIPT结果假阳性的重要原因。CPM可能与FGR有关。检测CPM的存在对于检测前和检测后的遗传咨询及孕期管理均具有重要意义。
