OBJECTIVE: To explore the phenotype and pathogenesis of a fetus with a rare chromosomal abnormality. METHODS: The fetus was analyzed by clinical prenatal ultrasonography, G-banding karyotyping and next generation sequencing (NGS). RESULTS: Prenatal ultrasonography of the fetus showed Dandy-Walker syndrome, growth restriction, and right-heart system dysplasia. The fetus had a chromosomal karyotype of 47,XY,t(11;22)(q23.3;q11.2),+der(22)t(11;22). Duplication of 11q23.3q25 and 22q11.1q21 were also detected by NGS. The chromosomal translocation carried by the fetus was derived from his father. CONCLUSION Duplications of chromosome 11q23.3q25 and 22q11.1q11.21 segments probably underlie the Dandy-Walker syndrome, growth restriction, and hypoplasia of the right heart system in the fetus.
Chromosome Disorders ; Chromosomes, Human ; Female ; Fetus ; Humans ; Karyotyping ; Pregnancy ; Prenatal Diagnosis ; Translocation, Genetic ; Trisomy

Objective: To investigate the correlation between fetal cranial nervous system malformation and chromosome abnormality. Methods: The pregnant women with fetal cerebral nervous system dysplasia were collected from January 2013 to August 2018 at the Prenatal Diagnostic Center of the Sixth Affiliated Hospital of Guangzhou Medical University.The fetus was diagnosed by ultrasonography and karyotype analysis. Results: A total of 18 cases of abnormal karyotypes were detected from 85 patient samples, and the abnormal rates were 21.18%.Single cranial nervous system malformation was found in 47 cases, abnormal karyotypes in 4 cases, multiple system malformation in 38 cases, and abnormal karyotypes in 14 cases, and the abnormal karyotype rate of multiple system malformation was higher than that of single cranial nervous malformation (36.84% vs.8.51%, χ²=10.101, P=0.001 5). And the 88.89%(16/18 cases)of abnormal karyotypes were founded in the early and middle pregnancy (≤28 weeks). The abnormal karyotype detection rates of cranial nervous system malformation associated with cardiovascular, skeletal and limb, facial neck abnormalities were 58.82% (10/17 cases), 50.00% (6/12 cases) and 50.00% (9/18 cases), respectively.In the fetal phenotypes, the abnormal karyotype detection rates of choroid plexus cysts were up to 64.29%, followed by arachnoid cysts (50.00%), craniocerebral abnormalities (45.45%) and holoprosencephaly (36.36%). Conclusions Chromosomal aneuploidy or structural abnormalities can lead to abnormal development of the fetal cranial nervous system, in which the rates of abnormal karyotypes on fetal cranial nervous with cardiovascular malformation and choroid plexus cysts are the highest.

Objective:To explore the prenatal ultrasound phenotype and genetic basis of two fetuses with Wolf-Hirschhorn syndrome (WHS).Methods:A retrospective analysis was conducted on the ultrasound imaging data of two fetuses suspected for WHS at the Prenatal Diagnostic Center of Qingyuan People′s Hospital in July 2017 and August 2019, respectively. Amniotic fluid samples of the two fetuses were subjected to chromosomal karyotyping and chromosomal microarray analysis (CMA). This study was approved by Medical Ethics Committee of the Qingyuan People′s Hospital (Ethics No. IRB-2022-064).Results:Prenatal ultrasound examination of the two fetuses had consistently revealed WHS-associated traits including intrauterine growth restriction (IUGR), craniofacial abnormalities and cardiovascular anomalies. Karyotyping analysis suggested that both fetuses had harbored cryptic chromosomal translocations involving partial deletion of 4p. And parental verification revealed that it was de novo for fetus 1 and paternal for fetus 2. CMA has confirmed that fetus 1 had an approximately 8.7 Mb deletion at 4p16.3p16.1 and a 6.8 Mb duplication at 8p23.1p23.1, whilst fetus 2 had a 20.05 Mb deletion at 4p16.3p15.31 and a 7.66 Mb duplication at 9p24.3p24.1. The karyotype of fetus 1 was determined as 46, XN, der(4)t(4; 8)(p16.1; p23.1)dn.arr[hg19]4p16.3p16.1(68345_8721580)×1, 8p23.3p23.1(158048_6933745)×3, and that of fetus 2 was determined as 46, XN, der(4)t(4; 9)(p15.3; p24)dpat.arr[hg19]4p16.3p15.31(68345_20116061)×1, 9p24.3p24.1(208454_7868292)×3. Conclusion:The 4p deletion is probably the main cause for the WHS phenotype in both fetuses. WHS should be suspected when IUGR, renal anomalies, craniofacial and cardiovascular abnormalities are detected upon prenatal ultrasound screening.