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 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 explore the diagnostic value of chromosome karyotype analysis, chromosomal microarray analysis (CMA) and whole exome sequencing (WES) in microcephaly.Methods:A total of 9 cases of microcephaly fetuses diagnosed by prenatal ultrasound or children with microcephaly diagnosed after birth were selected from the Sixth Affiliated Hospital of Guangzhou Medical University from January 2014 to August 2022.Karyotype analysis and/or CMA were used to detect. The cases with negative karyotype analysis and CMA results were further sequenced by trio-based WES (Trio-WES). Then the coding genes contained in the pathogenic copy number variation (CNV) fragments were analyzed by gene ontology (GO) enrichment. The genes related to the development of the central nervous system contained in the pathogenic CNV and the pathogenic genes found by Trio-WES were combined for gene interaction network analysis.Results:In this study, 9 cases of microcephaly were recruited, with the time of diagnosis ranged from 23 weeks of gestation to 7 years after birth, and the head circumference of fetus or children ranged from 18.3 to 42.5 cm (-7SD to -2SD). Karyotype analysis was detected in all 9 cases and no abnormality result was found. Eight cases were detected by CMA, and one abnormal was found. Five cases were detected by Trio-WES, and two cases were detected with likely pathogenic genes. The GO enrichment analysis of the coding gene in the 4p16.3 microdeletion (pathogenic CNV) region showed that: in biological process, it was mainly concentrated in phototransduction, visible light; in terms of molecular function, it was mainly concentrated in fibroblast growth factor binding; in terms of cell components, it was mainly concentrated in rough endoplasmic reticulum. Gene interaction network analysis suggested that CDC42 gene could interact with CTBP1, HTT and ASPM gene.Conclusions:CMA could be used as a first-line detection technique for microcephaly. When the results of chromosome karyotype analysis and/or CMA are negative, Trio-WES could improve the detection rate of pathogenicity of microcephaly.

Objective:To explore the application value of chromosome karyotype analysis, chromosomal microarray analysis (CMA) and whole exome sequencing (WES) in prenatal diagnosis of isolated corpus callosum abnormality (CCA) fetus.Methods:Fetuses diagnosed with isolated CCA by ultrasound and MRI and receiving invasive prenatal diagnosis in Guangzhou Women and Children′s Medical Center and Qingyuan People′s Hospital from January 2010 to April 2021 were selected. Karyotype analysis and/or CMA [or copy number variation sequencing (CNV-seq)] were performed on all fetal samples, and WES was performed on fetal samples and their parents whose karyotype analysis and/or CMA (or CNV-seq) results were not abnormal.Results:Among 65 fetuses with isolated CCA, 38 cases underwent karyotype analysis, and 3 cases were detected with abnormal karyotypes, with a detection rate of 8% (3/38). A total of 49 fetuses with isolated CCA underwent CMA (or CNV-seq) detection, and 6 cases of pathogenic CNV were detected, the detection rate was 12% (6/49). Among them, the karyotype analysis results were abnormal, and the detection rate of further CMA detection was 1/1. The karyotype results were normal, and the detection rate of further CMA (or CNV-seq) detection was 14% (3/21). The detection rate of CMA as the first-line detection technique was 7% (2/27). A total of 25 fetuses with isolated CCA with negative results of karyotyping and/or CMA were tested by WES, and 9 cases (36%, 9/25) were detected with pathogenic genes. The gradient genetic diagnosis of chromosomal karyotyping, CMA and WES resulted in a definite genetic diagnosis of 26% (17/65) of isolated CCA fetuses.Conclusions:Prenatal genetic diagnosis of isolated CCA fetuses is of great clinical significance. The detection rate of CMA is higher than that of traditional karyotyping. CMA detection could be used as a first-line detection technique for fetuses with isolated CCA. WES could increase the pathogenicity detection rate of fetuses with isolated CCA when karyotype analysis and/or CMA test results are negative.