Crouzon syndrome is the result of a gain-of-function point mutation in FGFR2. Mimicking the human mutation, a mouse model of Crouzon syndrome (Fgfr) recapitulates patient deformities, including failed tracheal cartilage segmentation, resulting in a cartilaginous sleeve in the homozygous mutants. We found that the Fgfr2 mutants exhibited an increase in chondrocytes prior to segmentation. This increase is due at least in part to over proliferation. Genetic ablation of chondrocytes in the mutant led to restoration of segmentation in the lateral but not central portion of the trachea. These results suggest that in the Fgfr2 mutants, increased cartilage cell proliferation precedes and contributes to the disruption of cartilage segmentation in the developing trachea.
Background: Goldenhar syndrome is a clinically heterogeneous disorder defined by a rare combination of congenital anomalies-an eye abnormality, in addition to two of the following three: ear anomalies, mandibular malformations, and vertebral defects. Notably, children with Goldenhar syndrome present with a high incidence of cervical spine malformations.
Clinical Case: In this report, we present an unusual case of a 15-year-old child with Goldenhar syndrome, who additionally presents with some clinical features of VACTERL syndrome.
Crouzon syndrome (CS) is a hereditary disorder characterized by deformities of the face and skull brought on by syndromic craniosynostosis or the premature fusion of coronal sutures. Pediatric patients with Crouzon syndrome have a high likelihood of developing obstructive sleep apnea (OSAS), primarily due to skeletal hypoplasia and facial dysmorphism. Treatment of OSAS in patients with Crouzon syndrome requires multidisciplinary and sequential treatment planning because Crouzon syndrome often has different phenotypes with varying severity in OSA and facial dysmorphism.
Treacher Collins syndrome, also known as mandibulofacial dysostosis, is a rare congenital disorder affecting craniofacial development. It is caused by an autosomal dominant mutation, primarily in the TCOF1 gene, which impacts the development of the first and second branchial arches. We present the case of a 12-year-old male with bilateral conductive hearing loss and deformed ears, whose clinical and imaging findings were consistent with Treacher Collins syndrome.
Treacher Collins syndrome (TCS) is a rare congenital craniofacial disorder with variable penetrance and high genetic and phenotypic heterogeneity. It is caused by pathogenic variants in the , , and genes, and its major characteristic features are malar and mandibular hypoplasia, downward slanting of the palpebral fissures, and conductive hearing loss. In this study, five patients (two males and three females, age range from 2 to 29 years) with TCS were tested by Next-Generation Sequencing (NGS)-based sequencing and clinically characterized.
