OBJECTIVE: To investigate the prenatal manifestation and genetic basis for two fetuses suspected for Osteocraniostenosis (OCS). METHODS: Two fetuses undergoing invasive prenatal diagnosis at Cangzhou People's Hospital in April and August 2021 for short long bones and abnormal skull morphology were selected as the study subjects. Clinical data were collected and analyzed. Genomic DNA was extracted from amniotic fluid and peripheral blood samples of the two couples. Candidate variants were validated by Sanger sequencing. Literature was retrieved from CNKI, Wanfang Data Knowledge Service Platform and PubMed using keywords including "FAM111A gene", "gracile bone dysplasia", "FAM111A" and "osteocraniostenosis" from January 1, 2000 to June 30, 2025. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: K2020-049). RESULTS: Fetus 1 was found to have short limbs, abnormal skull morphology and shallow cerebral sulci. Fetus 2 showed short limbs, irregular skull halo, prominent forehead and bilateral frontal narrowing. Trio-WES revealed that fetus 1 has carried a heterozygous missense variant c.1582G>C (p.Asp528His) in exon 4 of the FAM111A gene, which was unreported previously. Fetus 2 has harbored a heterozygous in-frame deletion c.1020_1022delTTC (p.Ser343del) in exon 6 of the FAM111A gene, which has been recorded as likely pathogenic by the ClinVar and HGMD databases. Sanger sequencing confirmed that the parents of both fetuses were wild-type for the variant sites. A total of 9 previously reported patients with FAM111A-related gracile bone dysplasia/OCS from 4 publications were retrieved. The main clinical features included intrauterine growth restriction, hypomineralized skull, gracile long bones with narrow medullary cavities and characteristic facial anomalies, which were in large in keeping with the prenatal features of the two fetuses. CONCLUSION Both fetuses were diagnosed with FAM111A-related OCS based on the characteristic prenatal findings and identification of the FAM111A variants. Above finding expanded the phenotypic spectrum of FAM111A-associated disorders and provided clues for the prenatal diagnosis and genetic counseling.
Humans ; Female ; Pregnancy ; Prenatal Diagnosis ; Phenotype ; Fetus ; Male ; Bone Diseases, Developmental/genetics* ; Adult

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 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 strategies of prenatal genetic testing for fetuses featuring abnormal skeletal development. METHODS: Clinical data of 17 fetuses with skeletal dysplasia was collected. The results of genetic testing and outcome of pregnancy were analyzed. RESULTS: For 12 fetuses, the femur-to-foot length ratio was less than 0.9. Thirteen fetuses had a positive finding by genetic testing. One fetus was diagnosed with chromosomal aneuploidy, three were diagnosed with microdeletion/microduplications, and nine were diagnosed with hereditary bone diseases due to pathological variants of FGFR3, COL1A2, GPX4 or ALPL genes. CONCLUSION For fetuses with skeletal dysplasia characterized by short femur, in addition to chromosomal karyotyping and microarray analysis, sequencing of FGFR3 and other bone disease-related genes can improve the diagnostic rate.
Bone Diseases, Developmental/genetics* ; Female ; Fetus/diagnostic imaging* ; Genetic Testing ; Humans ; Karyotyping ; Pregnancy ; Prenatal Diagnosis ; Receptor, Fibroblast Growth Factor, Type 3/genetics* ; Ultrasonography, Prenatal

No abstract available.
Bone Diseases, Developmental/diagnosis/drug therapy/*genetics ; Child ; Fibrillin-1/*genetics ; Hand/diagnostic imaging ; Heterozygote ; Human Growth Hormone/therapeutic use ; Humans ; Limb Deformities, Congenital/diagnosis/drug therapy/*genetics ; Male ; Pelvis/diagnostic imaging

KBG syndrome is a very rare genetic disorder characterized by macrodontia of upper central incisors, global developmental delay, distinctive craniofacial features, short stature, and skeletal anomalies. Ankyrin repeat domain 11 gene (ANKRD11) has recently been identified as a causal factor of this syndrome. We describe a 6-yr-old Korean boy with features of KBG syndrome. The patient had a short stature, macrodontia, dysmorphic facial features, speech and motor delay with intellectual disability, and partial seizures as indicated by the electroencephalogram, but he was neither autistic nor had autism spectrum disorders. Using high-resolution oligonucleotide array comparative genomic hybridization, we identified a heterozygous 240-kb deletion at 16q24.3 corresponding to ANKRD11. This patient provided additional evidence on the influence of ANKRD11 in KBG syndrome and suggested that deletion limited to ANKRD11 is unlikely to cause autism.
Abnormalities, Multiple/diagnosis/*genetics ; Asian Continental Ancestry Group/*genetics ; Bone Diseases, Developmental/diagnosis/*genetics ; Child ; Chromosomes, Human, Pair 16 ; Comparative Genomic Hybridization ; Electroencephalography ; Facies ; Gene Deletion ; Heterozygote ; Humans ; Intellectual Disability/diagnosis/*genetics ; Male ; Phenotype ; Repressor Proteins/*genetics ; Republic of Korea ; Tooth Abnormalities/diagnosis/*genetics