Department of Prenatal Diagnosis, Lianyungang Maternal and Child Health Hospital, Lianyungang, Jiangsu, 222000, People's Republic of China.
J Assist Reprod Genet. 2023 Sep;40(9):2233-2240. doi: 10.1007/s10815-023-02896-8. Epub 2023 Jul 28.
To report a rare type of Pallister-Killian syndrome (PKS) diagnosed prenatally by the utility of non-invasive prenatal testing (NIPT).
NIPT was performed in the first trimester. Conventional karyotyping and chromosomal microarray analysis (CMA) were performed on the amniotic samples in the second trimester. Copy number variation sequencing (CNV-seq) was used for the validation of fetal skin and the placental tissue after pregnancy termination.
NIPT results showed increased signal from chromosome 12p. Subsequent prenatal diagnostic testing by karyotype revealed 47, XY, +i (12p), and CMA displayed four copies of 12p: 12p13.33-12p11.1(173786_34835641) × 4. The CNV-seq results of the fetal skin and the fetal side of placenta showed four copies of 12p13.33-p11 and an estimated chimeric duplication of 34.08 Mb (chimerism ratio: 10%) in 12 p13.33-p11, respectively. However, no abnormality was detected by CNV-seq at the maternal side of placenta.
Our findings suggest that a positive signal from chromosome 12p on NIPT should raise suspicion for PKS. With the wide application of NIPT, the true positive of incidental finding is expected to increase.
报告一例通过无创产前检测（NIPT）诊断的罕见 Pallister-Killian 综合征（PKS）病例。
在孕早期进行 NIPT。在孕中期对羊水样本进行常规核型分析和染色体微阵列分析（CMA）。对终止妊娠后的胎儿皮肤和胎盘组织进行拷贝数变异测序（CNV-seq）验证。
NIPT 结果显示 12p 染色体信号增加。随后的核型产前诊断检测显示 47,XY,+i(12p)，CMA 显示 12p 的四个拷贝：12p13.33-12p11.1(173786_34835641)×4。胎儿皮肤和胎儿侧胎盘的 CNV-seq 结果显示 12p13.33-p11 存在四个拷贝，并且在 12p13.33-p11 处存在估计嵌合性重复 34.08Mb（嵌合率：10%）。然而，胎盘母体侧未通过 CNV-seq 检测到异常。
我们的研究结果表明，NIPT 上 12p 染色体的阳性信号应引起对 PKS 的怀疑。随着 NIPT 的广泛应用，预计偶然发现的真正阳性率将会增加。
