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BMJ Case Reports Jun 2024Goldenhar syndrome, also recognised as oculo-auriculo-vertebral spectrum, is a very rare condition distinguished by a diverse array of clinical abnormalities affecting...
Goldenhar syndrome, also recognised as oculo-auriculo-vertebral spectrum, is a very rare condition distinguished by a diverse array of clinical abnormalities affecting the ocular, auditory, vertebral and various organ systems. The pathophysiology of this condition is not fully elucidated due to its inherent genetic variability and rarity. In this report, we present a case of Goldenhar syndrome in a toddler boy, aiming to enhance the existing body of literature on this condition.
Topics: Humans; Goldenhar Syndrome; Male; Child, Preschool
PubMed: 38839403
DOI: 10.1136/bcr-2024-259872 -
International Journal of Molecular... Apr 2024Hemifacial microsomia (HFM) is a rare congenital genetic syndrome primarily affecting the first and second pharyngeal arches, leading to defects in the mandible,...
Hemifacial microsomia (HFM) is a rare congenital genetic syndrome primarily affecting the first and second pharyngeal arches, leading to defects in the mandible, external ear, and middle ear. The pathogenic genes remain largely unidentified. Whole-exome sequencing (WES) was conducted on 12 HFM probands and their unaffected biological parents. Predictive structural analysis of the target gene was conducted using PSIPRED (v3.3) and SWISS-MODEL, while STRING facilitated protein-to-protein interaction predictions. CRISPR/Cas9 was applied for gene knockout in zebrafish. In situ hybridization (ISH) was employed to examine the spatiotemporal expression of the target gene and neural crest cell (NCC) markers. Immunofluorescence with PH3 and TUNEL assays were used to assess cell proliferation and apoptosis. RNA sequencing was performed on mutant and control embryos, with rescue experiments involving target mRNA injections and specific gene knockouts. was identified as a novel candidate gene for HFM, with four nonsynonymous de novo variants detected in three unrelated probands. Structural predictions indicated significant alterations in the secondary and tertiary structures of . knockout in zebrafish resulted in craniofacial malformation, spine deformity, and cardiac edema, mirroring typical HFM phenotypes. Abnormalities in somatic cell apoptosis, reduced NCC proliferation in pharyngeal arches, and chondrocyte differentiation issues were observed in mutants. mRNA injections and or knockout significantly rescued pharyngeal arch cartilage dysplasia, while mRNA administration partially restored the defective phenotypes. Our findings suggest a functional link between and HFM, primarily through the inhibition of proliferation and disruption of pharyngeal chondrocyte differentiation.
Topics: Animals; Zebrafish; Humans; Male; Female; Goldenhar Syndrome; Apoptosis; Neural Crest; Exome Sequencing; Cell Proliferation; Phenotype; Mutation; Gene Knockout Techniques
PubMed: 38731925
DOI: 10.3390/ijms25094707 -
Prenatal Diagnosis Apr 2024Here we trained an automatic phenotype assessment tool to recognize syndromic ears in two syndromes in fetuses-=CHARGE and Mandibulo-Facial Dysostosis Guion Almeida type...
OBJECTIVE
Here we trained an automatic phenotype assessment tool to recognize syndromic ears in two syndromes in fetuses-=CHARGE and Mandibulo-Facial Dysostosis Guion Almeida type (MFDGA)-versus controls.
METHOD
We trained an automatic model on all profile pictures of children diagnosed with genetically confirmed MFDGA and CHARGE syndromes, and a cohort of control patients, collected from 1981 to 2023 in Necker Hospital (Paris) with a visible external ear. The model consisted in extracting landmarks from photographs of external ears, in applying geometric morphometry methods, and in a classification step using machine learning. The approach was then tested on photographs of two groups of fetuses: controls and fetuses with CHARGE and MFDGA syndromes.
RESULTS
The training set contained a total of 1489 ear photographs from 526 children. The validation set contained a total of 51 ear photographs from 51 fetuses. The overall accuracy was 72.6% (58.3%-84.1%, p < 0.001), and 76.4%, 74.9%, and 86.2% respectively for CHARGE, control and MFDGA fetuses. The area under the curves were 86.8%, 87.5%, and 90.3% respectively for CHARGE, controls, and MFDGA fetuses.
CONCLUSION
We report the first automatic fetal ear phenotyping model, with satisfactory classification performances. Further validations are required before using this approach as a diagnostic tool.
PubMed: 38635411
DOI: 10.1002/pd.6577 -
Science Progress 2024Treacher Collins syndrome (TCS) is a rare congenital craniofacial disorder, typically inherited as an autosomal dominant condition. Here, we report on a family in which... (Review)
Review
Treacher Collins syndrome (TCS) is a rare congenital craniofacial disorder, typically inherited as an autosomal dominant condition. Here, we report on a family in which germline mosaicism for TCS was likely present. The proband was diagnosed with TCS based on the typical clinical features and a pathogenic variant (c.4369_4373delAAGAA, p.K1457Efs*12). The mutation was not detected in his parents' peripheral blood DNA samples, suggesting a mutation had occurred in the proband. However, a year later, the proband's mother became pregnant, and the amniotic fluid puncture revealed that the fetus carried the same mutation as the proband. Prenatal ultrasound also indicated a maxillofacial dysplasia with unilateral microtia. The mother then disclosed a previous birth history in which a baby had died of respiratory distress shortly after birth, displaying a TCS-like phenotype. Around the same time, the proband's father was diagnosed with mild bilateral conductive hearing loss. Based on array data, we concluded that the father may have had germline mosaicism for mutation. Our findings highlight the importance of considering germline mosaicism in sporadic mutations when providing genetic consulting, and prenatal diagnosis is important when the proband's parents become pregnant again.
Topics: Humans; Pedigree; Mosaicism; Mandibulofacial Dysostosis; Mutation; Germ Cells
PubMed: 38629201
DOI: 10.1177/00368504241242278 -
Clinical Medicine & Research Mar 2024Goldenhar syndrome, a rare congenital anomaly, manifests as craniofacial malformations often necessitating intricate surgical interventions. These procedures, though...
Goldenhar syndrome, a rare congenital anomaly, manifests as craniofacial malformations often necessitating intricate surgical interventions. These procedures, though crucial, can expose patients to diverse postoperative complications, including hemorrhage or infection. A noteworthy complication is stroke, potentially linked to air embolism or local surgical trauma. We highlight a case of a male patient, aged 20 years, who experienced a significant postoperative complication of an ischemic stroke, theorized to be due to an air embolism, after undergoing orthognathic procedures for Goldenhar syndrome. The patient was subjected to LeFort I maxillary osteotomy, bilateral sagittal split ramus osteotomy of the mandible, and anterior iliac crest bone grafting to the right maxilla. He suffered an acute ischemic stroke in the left thalamus post-surgery, theorized to stem from an air embolism. Advanced imaging demonstrated air pockets within the cavernous sinus, a rare and concerning finding suggestive of potential air embolism. This case underscores the intricate challenges in treating Goldenhar syndrome patients and the rare but significant risk of stroke due to air embolism or surgical trauma. Limited literature on managing air embolism complications specific to Goldenhar syndrome surgeries exists. Generally, management includes immediate recognition, positional adjustments, air aspiration via central venous catheters, hyperbaric oxygen therapy, hemodynamic support, and high-flow oxygen administration to expedite air resorption. Our patient was conservatively managed post-surgery, and at a 3-month neurology follow-up, he showed significant improvement with only residual right arm weakness. It emphasizes the imperative of a comprehensive, multidisciplinary approach.
Topics: Humans; Male; Goldenhar Syndrome; Ischemic Stroke; Orthognathic Surgery; Embolism, Air; Stroke; Intraoperative Complications
PubMed: 38609140
DOI: 10.3121/cmr.2024.1882 -
Molecular Genetics & Genomic Medicine Apr 2024Mandibulofacial dysostosis with microcephaly (MFDM, OMIM# 610536) is a rare monogenic disease that is caused by a mutation in the elongation factor Tu GTP binding domain...
BACKGROUND
Mandibulofacial dysostosis with microcephaly (MFDM, OMIM# 610536) is a rare monogenic disease that is caused by a mutation in the elongation factor Tu GTP binding domain containing 2 gene (EFTUD2, OMIM* 603892). It is characterized by mandibulofacial dysplasia, microcephaly, malformed ears, cleft palate, growth and intellectual disability. MFDM can be easily misdiagnosed due to its phenotypic overlap with other craniofacial dysostosis syndromes. The clinical presentation of MFDM is highly variable among patients.
METHODS
A patient with craniofacial anomalies was enrolled and evaluated by a multidisciplinary team. To make a definitive diagnosis, whole-exome sequencing was performed, followed by validation by Sanger sequencing.
RESULTS
The patient presented with extensive facial bone dysostosis, upward slanting palpebral fissures, outer and middle ear malformation, a previously unreported orbit anomaly, and spina bifida occulta. A novel, pathogenic insertion mutation (c.215_216insT: p.Tyr73Valfs*4) in EFTUD2 was identified as the likely cause of the disease.
CONCLUSIONS
We diagnosed this atypical case of MFDM by the detection of a novel pathogenetic mutation in EFTUD2. We also observed previously unreported features. These findings enrich both the genotypic and phenotypic spectrum of MFDM.
Topics: Humans; Microcephaly; Mandibulofacial Dysostosis; Phenotype; Mutation; Intellectual Disability; Peptide Elongation Factors; Ribonucleoprotein, U5 Small Nuclear
PubMed: 38562046
DOI: 10.1002/mgg3.2426 -
International Journal of Biological... May 2024Treacher Collins syndrome-3 (TCS-3) is a rare congenital craniofacial disorder attributed to variants in the RNA pol I subunit C (POLR1C). The pathogenesis of TCS-3...
Treacher Collins syndrome-3 (TCS-3) is a rare congenital craniofacial disorder attributed to variants in the RNA pol I subunit C (POLR1C). The pathogenesis of TCS-3 linked to polr1c involves the activation of apoptosis-dependent p53 pathways within neural crest cells (NCCs). This occurs due to disruptions in ribosome biogenesis, and the restoration of polr1c expression in early embryogenesis effectively rescues the observed craniofacial phenotype in polr1c-deficient zebrafish. Clinical variability in TCS patients suggests interactions between genes and factors like oxidative stress. Elevated production of reactive oxygen species (ROS) in epithelial cells may worsen phenotypic outcomes in TCS individuals. Our study confirmed excessive ROS production in facial regions, inducing apoptosis and altering p53 pathways. Deregulated cell-cycle and epithelial-to-mesenchymal transition (EMT) genes were also detected in the TCS-3 model. Utilizing p53 inhibitor (Pifithrin-α; PFT-α) or antioxidants (Glutathione; GSH and N-Acetyl-L-cysteine; NAC) effectively corrected migrated NCC distribution in the pharyngeal arch (PA), suppressed oxidative stress, prevented cell death, and modulated EMT inducers. Crucially, inhibiting p53 activation or applying antioxidants within a specific time window, notably within 30 h post-fertilization (hpf), successfully reversed phenotypic effects induced by polr1c MO.
Topics: Animals; Zebrafish; Tumor Suppressor Protein p53; Mandibulofacial Dysostosis; Antioxidants; Disease Models, Animal; Benzothiazoles; Zebrafish Proteins; Oxidative Stress; Reactive Oxygen Species; Epithelial-Mesenchymal Transition; Toluene; Neural Crest; Apoptosis; RNA Polymerase I
PubMed: 38556235
DOI: 10.1016/j.ijbiomac.2024.131216 -
Scientific Reports Mar 2024Treacle ribosome biogenesis factor 1 (TCOF1) is responsible for about 80% of mandibular dysostosis (MD) cases. We have formerly identified a correlation between TCOF1...
Treacle ribosome biogenesis factor 1 (TCOF1) is responsible for about 80% of mandibular dysostosis (MD) cases. We have formerly identified a correlation between TCOF1 and CNBP (CCHC-type zinc finger nucleic acid binding protein) expression in human mesenchymal cells. Given the established role of CNBP in gene regulation during rostral development, we explored the potential for CNBP to modulate TCOF1 transcription. Computational analysis for CNBP binding sites (CNBP-BSs) in the TCOF1 promoter revealed several putative binding sites, two of which (Hs791 and Hs2160) overlap with putative G-quadruplex (G4) sequences (PQSs). We validated the folding of these PQSs measuring circular dichroism and fluorescence of appropriate synthetic oligonucleotides. In vitro studies confirmed binding of purified CNBP to the target PQSs (both folded as G4 and unfolded) with K values in the nM range. ChIP assays conducted in HeLa cells chromatin detected the CNBP binding to TCOF1 promoter. Transient transfections of HEK293 cells revealed that Hs2160 cloned upstream SV40 promoter increased transcription of downstream firefly luciferase reporter gene. We also detected a CNBP-BS and PQS (Dr2393) in the zebrafish TCOF1 orthologue promoter (nolc1). Disrupting this G4 in zebrafish embryos by microinjecting DNA antisense oligonucleotides complementary to Dr2393 reduced the transcription of nolc1 and recapitulated the craniofacial anomalies characteristic of Treacher Collins Syndrome. Both cnbp overexpression and Morpholino-mediated knockdown in zebrafish induced nolc1 transcription. These results suggest that CNBP modulates the transcriptional expression of TCOF1 through a mechanism involving G-quadruplex folding/unfolding, and that this regulation is active in vertebrates as distantly related as bony fish and humans. These findings may have implications for understanding and treating MD.
Topics: Animals; Humans; DNA; G-Quadruplexes; HEK293 Cells; HeLa Cells; Mandibulofacial Dysostosis; Nuclear Proteins; Phosphoproteins; RNA-Binding Proteins; Transcription Factors; Zebrafish
PubMed: 38553547
DOI: 10.1038/s41598-024-58255-9 -
Biochimica Et Biophysica Acta.... Apr 2024Nager syndrome (NS) is a rare acrofacial dysostosis caused by heterozygous loss-of-function variants in the splicing factor 3B subunit 4 (SF3B4). The main clinical...
Nager syndrome (NS) is a rare acrofacial dysostosis caused by heterozygous loss-of-function variants in the splicing factor 3B subunit 4 (SF3B4). The main clinical features of patients with NS are characterized by facial-mandibular and preaxial limb malformations. The migration and specification of neural crest cells are crucial for craniofacial development, and mitochondrial fitness appears to play a role in such processes. Here, by analyzing our previously published transcriptome dataset, we aim to investigate the potential involvement of mitochondrial components in the pathogenesis of craniofacial malformations, especially in sf3b4 mutant zebrafish. We identified that oxidative phosphorylation (OXPHOS) defects and overproduction of reactive oxygen species (ROS) due to decreased antioxidants defense activity, which leads to oxidative damage and mitochondrial dysfunction. Furthermore, our results highlight that fish lacking sf3b4 gene, primarily display defects in mitochondrial complex I. Altogether, our findings suggest that mitochondrial dysfunction may contribute to the development of the craniofacial anomalies observed in sf3b4-depleted zebrafish.
Topics: Animals; Gene Expression Profiling; Mandibulofacial Dysostosis; Mitochondrial Diseases; Mutation; RNA Splicing Factors; Zebrafish; Disease Models, Animal
PubMed: 38508476
DOI: 10.1016/j.bbadis.2024.167128