OBJECTIVE: To explore the genetic basis for a fetus with Cardiac-urogenital syndrome (CUGS). METHODS: A fetus with congenital heart disease identified at the Maternal Fetal Medical Center for Fetal Heart Disease, Beijing Anzhen Hospital Affiliated to Capital Medical University in January 2019 was selected as the study subject. Clinical data of the fetus was collected. Copy number variation sequencing (CNV-seq) and trio-whole exome sequencing (trio-WES) were carried out for the fetus and its parents. Candidate variants were verified by Sanger sequencing. RESULTS: Detailed fetal echocardiographic examination had revealed hypoplastic aortic arch. The results of trio-WES revealed that the fetus has harbored a de novo splice variant of the MYRF gene (c.1792-2A>C), for which both parents were of the wild-type. Sanger sequencing confirmed the variant to be de novo. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was rated as likely pathogenic. CNV-seq has identified no chromosomal anomalies. And the fetus was diagnosed with Cardiac-urogenital syndrome. CONCLUSION The de novo splice variant of the MYRF gene probably underlay the abnormal phenotype in the fetus. Above finding has enriched the spectrum of MYRF gene variants.
Female ; Humans ; DNA Copy Number Variations ; Fetal Diseases ; Fetus/abnormalities* ; Heart Defects, Congenital/genetics* ; Mutation ; Transcription Factors/genetics*

OBJECTIVE: To explore the clinical and genetic characteristics of a fetus with Melnick-Needles syndrome (MNS). METHODS: A fetus with MNS diagnosed at Ningbo Women and Children's Hospital in November 2020 was selected as the study subject. Clinical data was collected. Pathogenic variant was screened by using trio-whole exome sequencing (trio-WES). Candidate variant was verified by Sanger sequencing. RESULTS: Prenatal ultrasonography of the fetus had shown multiple anomalies including intrauterine growth retardation, bilateral femur curvature, omphalocele, single umbilical artery, and oligohydramnios. Trio-WES revealed that the fetus has harbored hemizygous c.3562G>A (p.A1188T) missense variant of the FLNA gene. Sanger sequencing confirmed that the variant was maternally derived, whilst its father was of a wild type. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was predicted to be likely pathogenic (PS4+PM2_Supporting+PP3+PP4). CONCLUSION The hemizygous c.3562G>A (p.A1188T) variant of the FLNA gene probably underlay the structural abnormalities in this fetus. Genetic testing can facilitate accurate diagnosis of MNS and provide a basis for genetic counseling for this family.
Child ; Female ; Humans ; Pregnancy ; Abnormalities, Multiple/genetics* ; Fetal Growth Retardation ; Fetus ; Filamins/genetics* ; Genetic Counseling ; Mutation ; Osteochondrodysplasias

OBJECTIVE: To assess the value of chromosomal microarray analysis (CMA) for the diagnosis of fetuses with anomalies of the central nervous system (CNS) and summarize the outcome of the pregnancies and follow-up. METHODS: A total of 636 fetuses from June 2014 to December 2020 who were referred to the Prenatal Diagnosis Center of Nanjing Drum Tower Hospital due to abnormal CNS prompted by ultrasound were selected as the research subjects. Based on the ultrasound findings, the fetuses were divided into ventricular dilatation group (n = 441), choroid plexus cyst group (n = 41), enlarged posterior fossa group (n = 42), holoprosencephaly group (n = 15), corpus callosum hypoplasia group (n = 22), and other anomaly group (n = 75). Meanwhile, they were also divided into isolated (n = 504) and non-isolated (n = 132) groups based on the presence of additional abnormalities. Prenatal samples (amniotic fluid/chorionic villi/umbilical cord blood) or abortus tissue were collected for the extraction of genomic DNA and CMA assay. Outcome of the pregnancies and postnatal follow-up were summarized and subjected to statistical analysis. RESULTS: In total 636 fetuses with CNS anomalies (including 89 abortus tissues) were included, and 547 cases were followed up. The overall detection rate of CMA was 11.48% (73/636). The detection rates for the holoprosencephaly group, ACC group, choroid plexus cyst group, enlarged posterior fossa group, ventricular dilatation group and other anomaly group were 80% (12/15), 31.82% (7/22), 19.51% (8/41), 14.29% (6/42), 7.48% (33/441) and 9.33% (7/75), respectively. Compared with the isolated CNS anomaly group, the detection rate for the non-isolated CNS anomaly group was significantly higher (6.35% vs. 31.06%) (32/504 vs. 41/132) (χ² = 62.867, P < 0.001). Follow up showed that, for 52 fetuses with abnormal CMA results, 51 couples have opted induced labor, whilst 1 was delivered at full term with normal growth and development. Of the 434 fetuses with normal CMA results, 377 were delivered at full term (6 had developmental delay), and 57 couples had opted induced labor. The rate of adverse pregnancy outcome for non-isolated CNS abnormal fetuses was significantly higher than that of isolated CNS abnormal fetuses (26.56% vs. 10.54%) (17/64 vs. 39/370) (χ² = 12.463, P < 0.001). CONCLUSION Fetuses with CNS anomaly should be tested with CMA to determine the genetic cause. Most fetuses with negative CMA result have a good prognosis, but there is still a possibility for a abnormal neurological phenotype. Fetuses with CNS abnormalities in conjunct with other structural abnormalities are at increased risk for adverse pregnancy outcomes.
Female ; Pregnancy ; Humans ; Holoprosencephaly ; Prenatal Diagnosis/methods* ; Central Nervous System ; Fetus/abnormalities* ; Nervous System Malformations/genetics* ; Microarray Analysis ; Central Nervous System Diseases ; Cysts ; Chromosome Aberrations ; Ultrasonography, Prenatal/methods*

OBJECTIVE: To explore the clinical characteristics and molecular genetic mechanism of a fetus with recombinant chromosome 8 (Rec8) syndrome. METHODS: A fetus who was diagnosed with Rec8 syndrome at the Provincial Hospital Affiliated to Shandong First Medical University on July 20, 2021 due to high risk for sex chromosomal aneuploidy indicated by non-invasive prenatal testing (NIPT) (at 21st gestational week) was selected as the study subject. Clinical data of the fetus was collected. G-banded karyotyping and chromosomal microarray analysis (CMA) were carried out on the amniotic fluid sample. Peripheral blood samples of the couple were also subjected to G banded karyotyping analysis. RESULTS: Prenatal ultrasonography at 23rd gestational week revealed hypertelorism, thick lips, renal pelvis separation, intrahepatic echogenic foci, and ventricular septal defect. The karyotype of amniotic fluid was 46,XX,rec(8)(qter→q22.3::p23.1→qter), and CMA was arr[GRCh37]8p23.3p23.1(158049_6793322)×1, 8q22.3q24.3(101712402_146295771)×3. The karyotype of the pregnant woman was 46,XX,inv(8)(p23.1q22.3), whilst that of her husband was normal. CONCLUSION The Rec8 syndrome in the fetus may be attributed to the pericentric inversion of chromosome 8 in its mother. Molecular testing revealed that the breakpoints of this Rec8 have differed from previously reported ones.
Humans ; Fetus/abnormalities* ; Chromosomes, Human, Pair 8 ; Female ; Pregnancy ; Karyotyping

OBJECTIVE: To explore the genetic basis for a fetus with limb abnormality and cardiac malformation. METHODS: Clinical data of a fetus diagnosed at the Shandong Provincial Maternal and Child Health Care Hospital on April 30th, 2021 was collected. Whole exome sequencing (WES) was carried out, and candidate variant was verified by Sanger sequencing and bioinformatic analysis. X-inactivation analysis was carried out for the female members of its family. RESULTS: The fetus was found to have meningoencephalocele, absence of bilateral radii, cleft lip, abnormal great arteries, and single umbilical artery at the gestational age of 11+ weeks. Sequencing revealed that the fetus has harbored a hemizygous c.1162del (p.Y388Tfs*7) variant of the FANCB gene, which was maternally inherited. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG) and ClinGen, the variant was classified as pathogenic (PVS1+PM2_Supporting+PP4). X-inactivation analysis has revealed complete skewed X-inactivation in the pregnant woman and her mother. CONCLUSION The hemizygous c.1162del (p.Y388Tfs*7) variant of the FANCB gene probably underlay the multiple malformations in this fetus.
Female ; Humans ; Pregnancy ; Abnormalities, Multiple ; Cleft Lip ; Fanconi Anemia Complementation Group Proteins ; Fetus ; Gestational Age ; Mothers

OBJECTIVE: To explore the genetic basis for a fetus with multiple malformations. METHODS: Clinical data of the fetus was collected, Amniotic fluid sample of the fetus was subjected to conventional G-banded karyotyping, low-depth whole genome copy number variants detection and whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing of the fetus and its parents. RESULTS: Prenatal ultrasound scan at 21⁺⁵ gestational weeks had revealed increased nuchal thickness (9.0 mm), enhanced echos of bilateral renal parenchyma, seroperitoneum, left pleural effusion and right displacement of the heart. The mother had a previous history of terminated pregnancy for multiple fetal anomalies. No abnormality was found by conventional karyotyping and CNV analysis, though WES revealed that the fetus has harbored a de novo heterozygous c.607C>T (p.Arg203Trp) variant of the ACS1 gene (NM_018026.3), and the result was validated by Sanger sequencing. CONCLUSION Through WES and prenatal ultrasonography, the fetus was diagnosed with Schuurs-Hoeijmakers syndrome due to the heterozygous c.607C>T (p.Arg203Trp) variant of the PACS1 gene (NM_018026.3). For fetuses with multiple malformations, WES can help to reveal the genetic etiology when CNV result is negative.
Female ; Pregnancy ; Humans ; Prenatal Diagnosis ; Ultrasonography, Prenatal ; Syndrome ; Fetus ; Abnormalities, Multiple ; Vesicular Transport Proteins

OBJECTIVE: To explore the genetic basis for fetuses with renal anomalies. METHODS: Genomic DNA of four fetuses and their parents was extracted from amniotic fluid and peripheral blood samples and subjected to whole genome sequencing. Candidate variants were predicted according to the American College of Medical Genetics and Genomics (ACMG) guidelines and validated by SNP-array and Sanger sequencing. RESULTS: Two fetuses were found to carry a 1.45 Mb pathogenic microdeletion in 17q12 and a pathogenic 1.85 Mb microduplication at 1q21.1-21.2, respectively. One fetus was found to harbor compound heterozygous variants c.8301del (p.Asn2768Thrfs*18) and c.4481del (p.Asn1494Thrfs*6) of the PKHD1 gene, which were predicted to be pathogenic. And one fetus has harbored homozygous c.1372dup (p.Thr458Asnfs*5) variants of the BBS12 gene, which was predicted to be likely pathogenic. All variants were validated by Sanger sequencing. CONCLUSION Whole genome sequencing can enable efficient prenatal diagnosis for fetuses with renal anomalies with high accuracy.
Female ; Fetus/abnormalities* ; Humans ; Pregnancy ; Prenatal Diagnosis ; Whole Genome Sequencing

OBJECTIVE: To assess the diagnostic value of copy number variation sequencing (CNV-seq) in the genetic etiology of fetuses with nasal bone dysplasia (NBD). METHODS: A total of 217 fetuses discovered with NBD from December 2017 to December 2020 were divided into the isolated NBD group and NBD combined with other anomalies group, for which copy number variations (CNVs) were analyzed. RESULTS: A total of 40 fetal abnormalities were detected in 217 cases, with an overall abnormal rate of 18.4%. These included 31 cases with aneuploidies (14.3%, 31/217) and 9 cases with genomic CNVs (4.1%, 9/217). Five cases of trisomy 21 (3.5%, 5/144) and two CNVs cases with unknown clinical significance (1.4%, 2/144) were detected in the isolated group. As for the combined NBD group, 26 aneuploidies (35.6%, 26/73), including 19 cases with trisomy 21, 6 cases with trisomy 18, 1 case with trisomy 13, 5 cases with pathogenic CNVs (6.8%, 5/73), and 2 cases with CNVs of unknown clinical significance (2.7%, 2/73) were detected. A significant difference was detected between the two groups (P < 0.01). CONCLUSION The detection rate of CNV-seq is high for chromosomal aneuploidies and pathogenic CNVs in fetuses with NBD, particularly in those combined with other ultrasonic abnormalities.
Aneuploidy ; Bone Diseases, Developmental ; Chromosome Aberrations ; DNA Copy Number Variations ; Down Syndrome/genetics* ; Female ; Fetus/abnormalities* ; Humans ; Pregnancy ; Prenatal Diagnosis ; Trisomy

OBJECTIVE: To explore the genetic basis for a fetus with dysgenesis of corpus callosum and other brain malformations. METHODS: Whole exome sequencing was carried out for the fetus and its parents. Suspected pathogenic variants were verified by Sanger sequencing. RESULTS: A novel de novo missense variant c.758T>A (p.L253Q) of the TUBB2B gene was identified, which was unreported previously. Based on the guidelines from the American College of Medical Genetics, the c.758T>A variant was predicted to be likely pathogenic. Bioinformatics analysis predicted that the leucine at position 253 was highly conserved among various species, and the c.758T>A variant may impact the formation of hydrogen bonds between Leu253 and Asp249 and Met257 residues, which in turn may affect the combination of GTP/GDP and function of the TUBB2B protein. CONCLUSION The c.758T>A variant of the TUBB2B gene probably underlay the fetal malformations in this Chinese family. Above discovery has enriched the spectrum of TUBB2B gene variants and provided a basis for genetic counseling and prenatal diagnosis.
Brain ; Female ; Fetus/abnormalities* ; Humans ; Malformations of Cortical Development/genetics* ; Pregnancy ; Prenatal Diagnosis ; Tubulin/genetics* ; Whole Exome Sequencing

OBJECTIVE: To analyze the phenotype and genetic variant of a fetus with dysplasia of cerebellar vermis. METHODS: Gestational status and family history of the gravida was taken in combination with the imaging results of the fetus. Following elected abortion, fetal tissue and peripheral blood samples of the couple were collected for the extraction of genome DNA. Whole exome sequencing was carried out to screen potential variant associated with the phenotype of the proband. Specific PCR primers were designed to verify the results by Sanger sequencing. RESULTS: Prenatal ultrasound revealed that the fetal vermis cerebellum was poorly developed, which was similar to the previous pregnancy. Whole exome sequencing revealed that the fetus has carried compound heterozygous variants of the CPLANE1 gene, namely c.7978C>T and c.7169delT, which were respectively inherited from the husband and wife. CONCLUSION The c.7978C>T and c.7169delT compound heterozygous variants of the CPLANE1 gene probably underlay the dysplasia of cerebellar vermis in the fetus, which has provided a basis for genetic counseling and prenatal diagnosis.
Abnormalities, Multiple/genetics* ; Cerebellum/diagnostic imaging* ; Eye Abnormalities/genetics* ; Female ; Fetus ; Humans ; Kidney Diseases, Cystic ; Mutation ; Phenotype ; Pregnancy ; Retina/abnormalities*