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 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

Ectodermal Dysplasia ; complications ; diagnostic imaging ; pathology ; Female ; Humans ; Hydrocephalus ; complications ; diagnostic imaging ; pathology ; Infant ; Polydactyly ; complications ; Tomography, X-Ray Computed