Study of a fetus with confined placental mosaicism for trisomy 2 in conjunct with fetal uniparental disomy and a literature review.
10.3760/cma.j.cn511374-20220524-00348
- Author:
Chunqiang LIU
1
;
Yan LYU
;
Yulin JIANG
;
Qingwei QI
;
Xiya ZHOU
;
Na HAO
;
Mengmeng LI
;
Mouhuizi GAI
Author Information
1. Center of Prenatal Diagnosis, Quanzhou Maternal and Child Health Care Hospital, Children's Hospital, Quanzhou, Fujian 362017, China. lvyan@pumch.cn.
- Publication Type:Review
- MeSH:
Female;
Humans;
Pregnancy;
Amniocentesis;
Chromosomes, Human, Pair 2/genetics*;
DNA Copy Number Variations;
Fetal Death;
Fetal Growth Retardation/genetics*;
Fetus;
Mosaicism;
Oligohydramnios;
Placenta;
Trisomy/genetics*;
Uniparental Disomy/genetics*
- From:
Chinese Journal of Medical Genetics
2023;40(12):1461-1465
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE:To carry out genetic analysis for a fetus with confined placental mosaicism (CPM) for trisomy 2 (T2) in conjunct with fetal uniparental disomy (UPD).
METHODS:Amniocentesis and chromosomal karyotyping was carried out for a pregnant woman with a high risk for chromosome 2 anomalies indicated by non-invasive prenatal testing (NIPT). Single nucleotide polymorphism array (SNP-array) and trio-whole exome sequencing (Trio-WES) were carried out. Ultrasonography was used to closely monitor the fetal growth. Multifocal sampling of the placenta was performed after delivery for copy number variation sequencing (CNV-seq).
RESULTS:The fetus was found to have a normal chromosomal karyotype. SNP-array has revealed multiple regions with loss of heterozygosity (LOH) on chromosome 2. Trio-WES confirmed the presence of maternal UPD for chromosome 2. Ultrasonography has revealed intrauterine growth restriction and oligohydramnios. Intrauterine fetal demise had occurred at 23+4 weeks of gestation. Pathological examination had failed to find salient visceral abnormality. The placenta was proved to contain complete T2 by CNV-seq.
CONCLUSION:T2 CPM can cause false positive result for NIPT and may be complicated with fetal UPD, leading to adverse obstetric outcomes such as intrauterine growth restriction, oligohydramnios and intrauterine fetal demise.
