OBJECTIVE: To explore the prenatal and postnatal phenotypes of 22q11.2 microdeletion syndrome (22q11.2DS) and enhance clinical understanding of this condition. METHODS: Data were collected from 86 fetuses diagnosed with 22q11.2DS at four prenatal diagnostic centers across China between January 2014 and August 2025. Prenatal imaging findings, pregnancy outcomes, and postnatal conditions were analyzed. RESULTS: Among the 86 fetuses, complete ultrasound data were available for 65 cases. Cardiovascular abnormalities were observed in 42 cases, thymic hypoplasia or aplasia in 7 cases, urinary system anomalies in 6 cases, nuchal translucency (NT) thickening in 7 cases, butterfly vertebrae, clubfoot, omphalocele and diaphragmatic hernia in 1 case each, cleft lip and palate in 2 cases, and ultrasound soft markers in 13 cases. The parents of 9 fetuses opted to continue with the pregnancy. Among these, 6 showed no significant ultrasound abnormalities and no related phenotypes postnatally, while the remaining 3 exhibited ultrasound anomalies with postnatal manifestations including developmental delay, immunodeficiency, and cardiac defects. CONCLUSION Fetuses with 22q11.2DS may exhibit various ultrasound abnormalities in multiple systems before and after birth. In addition to cardiovascular anomalies, they may also present with thymic hypoplasia or aplasia, thickened NT, and urinary abnormalities. Fetuses with thickened NT or thymic anomalies should be closely monitored, and thymic assessment should be included in routine prenatal imaging evaluations. For fetuses with 22q11.2DS who show no ultrasound abnormalities, the risk of developing severe phenotypes after birth is relatively low, but occult palate clefts and psychiatric disorders cannot be ruled out. Due to limitations in sample size and follow-up duration, above conclusions require further validation through large-scale prospective studies.
Humans ; Female ; Pregnancy ; Ultrasonography, Prenatal ; DiGeorge Syndrome/genetics* ; Adult ; Male ; Follow-Up Studies ; Fetus/diagnostic imaging* ; Phenotype ; Infant, Newborn

OBJECTIVE: To investigate the genetic etiology of a fetus diagnosed with Mandibulofacial dysostosis with microcephaly (MFDM). METHODS: A fetus that underwent prenatal diagnosis at Beijing Obstetrics and Gynecology Hospital, Capital Medical University, on May 19, 2025 was selected for analysis. Results of fetal ultrasound findings, chromosomal karyotyping, copy number variation sequencing (CNV-seq), and whole-exome sequencing (WES) were collected. Sanger sequencing was performed for familial validation of the pathogenic variant. The Human Protein Atlas (HPA), STRING, and Simple ClinVar databases were queried to characterize the biological features of the candidate gene. Three-dimensional structures of the wild-type and variant proteins were modeled and analyzed, and the evolutionary conservation of the affected amino acid was assessed using UGENE. Prenatal phenotypes associated with EFTUD2 variants were summarized through a review of the literature. This study was approved by the Ethics Committee of Beijing Obstetrics and Gynecology Hospital, Capital Medical University (Ethics No.: 2025-KY-029-01). RESULTS: At 23⁺² weeks of gestation, ultrasound examination revealed bilateral microtia with low-set ears, mild micrognathia with a reduced mandibular-facial angle, a single umbilical artery, a slightly narrow aortic diameter, and trivial mitral regurgitation. Amniotic fluid karyotyping and CNV-seq showed no abnormalities. WES identified a de novo, previously unreported EFTUD2 variant, c.698dupA (p.V235Gfs*27), in the fetus. This frameshift variant is predicted to alter the structural integrity of the EFTUD2 protein. Literature review indicated that micrognathia and microtia or low-set ears are the most common sonographic features in fetuses with EFTUD2 variants, while secondary findings may include abnormal stomach bubble, cleft palate, single umbilical artery, gastrointestinal atresia, polyhydramnios, and reduced aortic diameter. CONCLUSION The EFTUD2: c.698dupA (p.V235Gfs*27) variant is likely the genetic cause underlying MFDM in this fetus.
Humans ; Mandibulofacial Dysostosis/diagnostic imaging* ; Microcephaly/diagnostic imaging* ; Female ; Pregnancy ; Ribonucleoprotein, U5 Small Nuclear/chemistry* ; Peptide Elongation Factors/chemistry* ; Fetus ; DNA Copy Number Variations/genetics* ; Adult ; Ultrasonography, Prenatal

OBJECTIVE: To explore the clinical phenotype, pregnancy outcome and follow-up of fetuses with 15q11.2BP1-BP2 microdeletions in order to provide a basis for prenatal and reproductive consultation. METHODS: From March 2019 to December 2023, 20 fetuses who were diagnosed with 15q11.2BP1-BP2 microdeletion syndrome at the Prenatal Diagnosis Center of General Hospital of Ningxia Medical University were selected as the study subjects. Results of genetic testing and ultrasound examination, outcome of pregnancy, and postnatal follow-up were retrospectively analyzed. This study has been approved by the Ethics Committee of General Hospital of Ningxia Medical University ([2020]0520B). RESULTS: None of the 20 fetuses was found to have chromosomal abnormality, whilst all were found to harbor a 15q11.2 BP1-BP2 microdeletion by low-depth whole genome sequencing (CNV-seq). The range of deletions was determined as 0.26 ~ 0.87 Mb, and all were rated as pathogenic CNVs. Three fetuses had abnormal ultrasound findings, including 1 with widened renal pelvis, 1 with agenesis of corpus callosum, and 1 with nuchal fold thickening. Parental verification in 10 couples verified that two fetal deletions were de novo, whilst the remaining eight were inherited from a phenotypically normal parent. Following genetic counseling, three couples had opted to terminate the pregnancy, whilst the remaining 17 had continued with the pregnancy until delivery. The 17 liveborns were followed up for 2 months to 5 years, with no obvious abnormality in growth and development noted. CONCLUSION CNV-seq plays an important role in the prenatal diagnosis of 15q11.2 BP1-BP2 microdeletions. Such deletions may not always lead to disease phenotypes. Individualized consultation and long-term follow-up, in combination with intrauterine ultrasound and parental verification are necessary.
Humans ; Female ; Pregnancy ; Chromosomes, Human, Pair 15/genetics* ; Genetic Counseling ; Prenatal Diagnosis ; Chromosome Deletion ; Adult ; Fetus/abnormalities* ; Retrospective Studies ; Pregnancy Outcome ; Ultrasonography, Prenatal ; Genetic Testing ; DiGeorge Syndrome/diagnosis* ; Male

OBJECTIVE: To carry out genetic testing on two fetuses with prenatal ultrasound finding of polydactyly and renal abnormalities to determine the underlying causes. METHODS: Two fetuses with structural abnormalities detected by prenatal ultrasound at Cangzhou People's Hospital in 2021 were selected as the study subjects. Genomic DNA was extracted from the muscle tissue of the abortus and peripheral blood samples from both parents. Whole-exome sequencing (WES) was conducted on the trio to detect the genetic variants. Quantitative PCR was used to validate the exonic deletions. This study has been approved by the Ethics Committee of Cangzhou People's Hospital (Ethics No.K2020-049). RESULTS: Prenatal ultrasound revealed postaxial polydactylies of fingers and toes and slightly enlarged kidneys with increased echogenicity in fetus 1, along with polydactyly of both hands, enlarged kidneys, and enhanced echogenicity of renal parenchyma in fetus 2. Trio-WES analysis revealed that fetus 1 has harbored a pathogenic c.1339G>A variant of the BBS1 gene, along with a heterozygous 426 bp deletion in the 11q13.2 region, which was unreported previously. The deletion has involved exons 10 and 11 of the BBS1 gene. The two variants were inherited from its mother and father, respectively. Fetus 2 was found to harbor a pathogenic c.539G>A variant and a likely pathogenic c.49G>A variant of the BBS10 gene, which were inherited from its mother and father, respectively. The c.49G>A variant has not been documented in databases and the literature. CONCLUSION Two rare fetuses with Bardet-Biedl syndrome have been diagnosed. Above finding has expanded the mutational spectrum of this syndrome and has important implications for genetic counseling for the affected families.
Humans ; Bardet-Biedl Syndrome/diagnostic imaging* ; Female ; Pregnancy ; Fetus/abnormalities* ; Ultrasonography, Prenatal ; Phenotype ; Polydactyly/diagnostic imaging* ; Exome Sequencing ; Adult ; Genetic Testing ; Male ; Prenatal Diagnosis ; Group II Chaperonins/genetics* ; Microtubule-Associated Proteins

OBJECTIVE: To explore the genetic etiology of fetal skeletal dysplasia using whole exome sequencing (WES) and copy number variation sequencing (CNV-seq) techniques, and the feasibility of using WES as the first-tier method for such fetuses. METHODS: Seventy four fetuses with skeletal dysplasia detected by prenatal ultrasound at the Genetic Testing Center of the Women and Children's Hospital Affiliated to Qingdao University from January 2020 to August 2024 were selected as the study subjects. Fetal muscle and peripheral blood samples of the pregnant women and their spouses were collected and subjected to WES analysis. CNV-seq was carried out on all fetal muscle tissue samples. And the results were compared with the CNVs indicated by WES. Genetic etiologies were analyzed across different subtypes of skeletal dysplasia. And the feasibility of using WES as the first-tier genetic test for similar fetuses was assessed, in addition with a systematic cost-effectiveness analysis. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: QFELL-YJ-2024-201). RESULTS: A total of 50 fetuses were diagnosed, which yielded a diagnostic rate of 67.57%. These included 6 chromosomal aneuploidies, 4 chromosomal CNVs and 40 monogenic disorders. The monogenic diseases had involved 46 variant sites in 23 pathogenic genes, among which 12 were unreported previously, including MYH3: c.735T>C, ALPL: c.1324C>T, NEK9: c.1973G>A, MAGEL2: c.2024_2025del, LMBR1: c.423+4914A>C, NEB: c.21273_21276del, COL1A1: c.2651G>C and c.2758G>C, ASPM: c.2473delinsGA, TBX5: c.704G>A, DYNC2H1: c.10893del, and DYNC2I2: c.1270C>T. Substantial concordance was reached between WES-derived CNV calls and CNV-seq findings. No clinically significant CNV was exclusively detected by CNV-seq. Cost-effectiveness modeling demonstrated that implementing WES as the first-tier genetic testing method could reduce the total expenditure when WES unit cost remained below 6.4 folds that of the CNV-seq. CONCLUSION Genetic variants including single nucleotide variations (SNV) of monogenic disorders, chromosomal aneuploidies and genomic CNVs are important causes for fetal skeletal dysplasia. WES is an accurate and efficient method for analyzing the etiology of fetal skeletal dysplasia, particularly in those with a family history of similar phenotype or maternal history of adverse pregnancies.
Humans ; Exome Sequencing/methods* ; Female ; Pregnancy ; DNA Copy Number Variations/genetics* ; Genetic Testing/methods* ; Prenatal Diagnosis/methods* ; Adult ; Male ; Fetus ; Bone Diseases, Developmental/diagnosis* ; Ultrasonography, Prenatal

OBJECTIVE: To explore the clinical and genetic characteristics of fetuses with Kabuki syndrome (KS) and their genotype-phenotype correlation. METHODS: A retrospective analysis was carried out on the prenatal manifestations and results of genetic testing of six KS fetuses diagnosed by whole-exome sequencing (WES). The findings were compared with 28 prenatally diagnosed KS cases reported in the literature to summarize the prenatal features of KS. This study has been approved by the Ethics Committee of Maternal and Child Health Care Hospital of Hubei Province (Ethics No.: 2025-141-01). RESULTS: Prenatal ultrasound findings in KS fetuses showed high heterogeneity. The most common abnormalities were cardiac (23/35, 65.7%) and renal (20/35, 57.1%), which are often accompanied by amniotic fluid abnormalities (5/35, 14.3%), single umbilical artery (5/35, 14.3%), and fetal hydrops (4/35, 11.4%). Among the six fetuses from our center, all were identified by WES to harbor pathogenic variants of the KMT2D gene, and all of which were de novo. These included 3 frameshift variants, 2 nonsense variant, and 1 missense variant, among which 4 were unreported previously. CONCLUSION This study has expanded the mutational spectrum of the KMT2D gene. Prenatal ultrasound findings of KS lack specificity, though multi-system anomalies or specific soft markers may indicate KS. WES is an effective tool for the diagnosis, and KS should be included in the differential diagnosis list for prenatal cardiac and renal abnormalities.
Humans ; Hematologic Diseases/diagnostic imaging* ; Face/diagnostic imaging* ; Female ; Vestibular Diseases/diagnostic imaging* ; Abnormalities, Multiple/diagnostic imaging* ; Pregnancy ; Ultrasonography, Prenatal ; Adult ; Neoplasm Proteins/genetics* ; Retrospective Studies ; DNA-Binding Proteins/genetics* ; Male ; Exome Sequencing ; Fetus/diagnostic imaging* ; Genetic Association Studies ; Mutation

OBJECTIVE: To explore the detection rate of copy number variations (CNVs) in fetuses with isolated Congenital anomalies of the kidney and urinary tract (CAKUT) and pregnancy outcomes in order to provide a basis for genetic counseling. METHODS: One hundred and eighty eight fetuses who underwent chromosomal microarray analysis (CMA) due to isolated CAKUT detected by prenatal ultrasonography at Qingdao Women and Children's Hospital from January 2021 to December 2024 were selected as the study subjects. According to the ultrasound findings, the fetuses were divided into 8 groups, including renal parenchymal dysplasia group, renal cystic dysplasia group, simple renal parenchymal echo enhancement group, abnormal development of renal collecting system group, duplicated kidney group, ectopic kidney group, horseshoe kidney group, and bladder/posterior urethral abnormalities group. The detection of CNVs was retrospectively analyzed, and the pregnant women were followed up to summarize their pregnancy outcomes. 2 test (or Fisher's exact probability method) was used to compare the CNV detection rates between the groups. This study was approved by the Medical Ethics Committee of the Qingdao Women and Children's Hospital (Ethics No.: QFELL-YJ-2025-85). RESULTS: Among the 188 fetuses with isolated CAKUT, 23 CNVs (12.23%) were detected, of which 13 cases (6.91%) were pathogenic and 10 cases were rated as variants of unknown significance (VOUS). Among the 8 groups, the three groups with the highest proportion were renal cystic dysplasia group, renal metaplasia group, and renal parenchymal dysplasia group. The detection rates of pathogenic CNVs in the three groups were 1.79% (1/56), 6.78% (4/59), and 16.67% (5/30), respectively, with statistically significant differences (P < 0.05). Parental verification was conducted on 12 fetuses detected with the CNVs, confirming that 2 cases were de novo and 10 were inherited from parents with a normal phenotype. After genetic counseling, the parents of 9 fetuses opted to terminate the pregnancy, while 11 chose to continue with the pregnancy, and 3 were lost to follow-up. At the time of last follow-up, the youngest offspring was 5 months old and the oldest was 3 years and 11 months old. One child had renal aplasia, and two were born with hydronephrosis, which have been cured through surgery. The remainders had no obvious abnormality with their growth and development. CONCLUSION CMA testing has important value for prenatal diagnosis of isolated CAKUT. In this study, the detection rate of pathogenic CNVs has increased sequentially in fetuses with renal cystic developmental abnormalities, renal collecting system developmental abnormalities, and renal parenchymal dysplasia, while there was no significant difference in the detection rate of CNVs. For fetuses with isolated CAKUT detected by prenatal ultrasound, CMA testing should be considered, and reasonable pregnancy decisions should be made based on the results of prenatal ultrasound and parental verification.
Humans ; Female ; Pregnancy ; Prenatal Diagnosis/methods* ; DNA Copy Number Variations/genetics* ; Kidney/abnormalities* ; Adult ; Ultrasonography, Prenatal ; Urogenital Abnormalities/diagnosis* ; Microarray Analysis/methods* ; Retrospective Studies ; Urinary Tract/abnormalities* ; Fetus ; Pregnancy Outcome ; Vesico-Ureteral Reflux

OBJECTIVE: To explore the prenatal features and genetic etiology of a fetus with Short-rib cage dysplasia (SRTD) due to variants of DYNC2H1 gene. METHODS: A pregnant women presented at Xinxiang Central Hospital in June 2020 for abnormal prenatal ultrasound findings was selected as the study subject. With informed consent obtained, amniotic fluid sample was extracted from the woman, and clinical data of the fetus were collected. Whole exome sequencing (WES) was carried out, and candidate variants were verified by Sanger sequencing. This study was approved by the Medical Ethics Committee of Xinxiang Central Hospital [Ethics No.: 2025-214-01(K)]. RESULTS: At 25⁺⁶ weeks gestation, genetic testing revealed that the fetus has harbored compound heterozygous variants of the DYNC2H1 gene, namely c.10585C>T (p.Arg3529Ter) and c.8954T>G (p.Val2985Gly), which were derived from its father and mother, respectively. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the c.10585C>T (p.Arg3529Ter) and c.8954T>G (p.Val2985Gly) variants were classified as pathogenic (PVS1+PM2_supporting+PM3+PP5) and likely pathogenic (PM1+PM2_supporting+PM3+PP3), respectively. Bioinformatics analysis suggested that both variants may affect the 3D structure of the DYNC2H1 protein. CONCLUSION The compound heterozygous variants of c.10585C>T (p.Arg3529Ter) and c.8954T>G (p.Val2985Gly) of the DYNC2H1 gene probably underlay the pathogenesis of SRTD in the fetus. Above findings had facilitated prenatal diagnosis and genetic counseling for the couple.
Humans ; Female ; Pregnancy ; Cytoplasmic Dyneins/chemistry* ; Prenatal Diagnosis ; Adult ; Short Rib-Polydactyly Syndrome/diagnostic imaging* ; Mutation ; Exome Sequencing ; Fetus/abnormalities* ; Ultrasonography, Prenatal

OBJECTIVE: To investigate the clinical characteristics and genetic etiology in a fetus with 12q14 microdeletion syndrome. METHODS: A fetus diagnosed with 12q14 microdeletion syndrome at Wenzhou People's Hospital in July 2019 was selected as the study subject. The fetus was from a twin pregnancy by in vitro fertilization-embryo transfer, with ultrasound findings including growth restriction, cleft lip/palate, ventricular septal defect, tricuspid regurgitation, and pericardial effusion. Clinical data and family history were collected. Amniotic fluid sample was collected from both twins, and peripheral blood samples were obtained from their parents. Amniocytic karyotyping analysis and chromosomal microarray analysis (CMA) were performed, and familial validation was conducted. This study was approved by the Medical Ethics Committee of Wenzhou People's Hospital (Ethics No.: KY-202408-034). RESULTS: Prenatal ultrasound showed no significant abnormality in one of the twins, whilst the other twin exhibited severe growth restriction accompanied by cleft lip/palate, ventricular septal defect, tricuspid regurgitation, and pericardial effusion. Karyotyping and CMA analyses of first twin showed no abnormalities, whilst the second twin had a chromosomal karyotype of 46,XN,t(3;12)(q26.3;q14), and CMA revealed a 4.9 Mb deletion in the 12q14.3-q15 region (arr[hg19]12q14.3q15(65,574,059_70,488,106)x1). Karyotyping and CMA analyses of both parents revealed no abnormalities, confirming that the fetus deletion was de novo in origin. Literature review suggested that prenatal diagnosis of 12q14 microdeletion syndrome has been extremely rare. CONCLUSION The fetus was diagnosed with 12q14 microdeletion syndrome. This de novo deletion may have dervied from chromosomal translocation. As a first-tier prenatal diagnostic technique, CMA can effectively detect microdeletion/microduplications missed by conventional karyotyping analysis.
Humans ; Female ; Pregnancy ; Chromosome Deletion ; Chromosomes, Human, Pair 12/genetics* ; Karyotyping ; Adult ; Prenatal Diagnosis ; Chromosome Disorders/diagnosis* ; Ultrasonography, Prenatal ; Fetus ; Male

BACKGROUND

Down syndrome or trisomy 21, the most common chromosomal disorder, results from the presence of a third copy of chromosome 21 and manifests as mild to moderate intellectual disability, growth retardation, congenital heart defects, gastrointestinal abnormalities, and characteristic facial features. Several methods have been used to screen for Down syndrome in the prenatal period, such as ultrasound, biomarkers, cell-free DNA testing, and combinations of these tests. A positive result from one or more of these screening tests signals the need for confirmatory karyotyping to clinch the diagnosis. Ultrasound between 11 to 14 weeks of gestation can evaluate nuchal translucency (NT) to screen for Down syndrome. During the second trimester, a triple or quadruple test can also be performed alone or in addition to NT to quantify Down syndrome risk. In limited resource settings however, only the measurement of NT via ultrasound can be performed since biomarker tests are either unavailable or inaccessible. While the diagnostic performance of NT measurement alone has been investigated in several observational studies, there is no consensus on its performance as a sole test to screen for Down syndrome.

To determine the diagnostic performance of NT during prenatal first-trimester ultrasound as a screening test for Down syndrome.

We performed a systematic search on the PubMed, ProQuest, and Cochrane Library databases for recent systematic reviews and meta-analyses that addressed the objective. The existing reviews found were then independently appraised by the two reviewers with the AMSTAR-2 checklist. To update the existing reviews, a systematic search was done in the same databases to identify additional primary diagnostic studies, which were appraised using the QUADAS-2 tool. Random-effects univariate meta-analysis and summary receiving operator curve (HSROC) analysis for the outcomes were performed using Review Manager version 5.4 and R version 4.2.2, respectively. Subgroup analysis was performed by stratifying the baseline risk of mothers for fetal anomaly as low- or high-risk. Highrisk mothers were defined as women with risk factors such as advanced age, positive serum screen, presence of other ultrasound anomalies, and history of previous fetus with anomaly.

We found 22 cohort studies (n=225,846) of women at low-risk for fetal anomaly. The pooled sensitivity was 67.8% (95% CI: 61.4%-73.6%, I2=70.4%) and specificity was 96.3% (95% CI: 95.5%-96.9%, I2=96.7%). For low-risk women, the overall certainty of evidence was low, due to different modes of verification and heterogeneity not completely explained by variability in baseline risk or cut-points. Seven studies (n=9,197) were on high-risk women. The pooled sensitivity was 62.2% (95% CI: 54.1%-69.7%, I2=38.8%) and specificity was 96.5% (95% CI: 93.6%-98.1%, I2=95.5%). For women at high-risk, the evidence was rated as moderate due to differential verification.

Our analysis showed that NT measured through first-trimester ultrasound is specific for Down syndrome but has low sensitivity. Despite this, it is a useful screening test for Down syndrome in low-resource settings where other strategies may not be available or accessible. Furthermore, interpretation of NT results must take into consideration its limited sensitivity as this may lead to missed cases.