Fetal growth restriction (FGR), a leading cause of perinatal morbidity and mortality, is caused by fetal, maternal, and placental factors. Uniparental disomy (UPD) is a rare condition that leads to imprinting effects, low-level mosaic aneuploidies and homozygosity for pathogenic variants. In the present study, UPD events were detected in 5 women with FGR by trio exome sequencing (trio-WES) of a cohort of 150 FGR cases. Furthermore, noninvasive prenatal testing results of the 5 patients revealed a high risk of rare autosomal trisomy. Trio-WES showed no copy-number variations (CNVs) or nondisease-causing mutations associated with FGR. Among the 5 women with FGR, two showed gene imprinting, and two exhibited confined placental mosaicism (CPM) by copy number variant sequencing (CNV-seq). The present study showed that in FGR patients with UPD, the detection of imprinted genes and CPM could enhance the genetic diagnosis of FGR.

胎儿生长受限（FGR）是围产期发病和死亡的主要原因，由胎儿、母体和胎盘因素引起。单亲二倍体 (UPD) 是一种罕见的疾病，会导致印记效应、低水平嵌合非整倍体和致病性变异的纯合性。在本研究中，通过三重外显子组测序 (trio-WES) 对 150 例 FGR 病例进行队列检测，发现 5 名 FGR 女性存在 UPD 事件。此外，5名患者的无创产前检测结果显示，患有罕见常染色体三体性的风险很高。 Trio-WES 显示没有拷贝数变异 (CNV) 或与 FGR 相关的非致病突变。通过拷贝数变异测序 (CNV-seq)，在 5 名患有 FGR 的女性中，两名显示出基因印记，两名显示出局限性胎盘嵌合体 (CPM)。本研究表明，在FGR合并UPD的患者中，印迹基因和CPM的检测可以增强FGR的基因诊断。