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Pediatric Neurology Nov 2012Epilepsy, a neurologic disorder characterized by the predisposition to recurrent unprovoked seizures, is reported in more than 300 genetic syndromes. Muenke syndrome is... (Review)
Review
Epilepsy, a neurologic disorder characterized by the predisposition to recurrent unprovoked seizures, is reported in more than 300 genetic syndromes. Muenke syndrome is an autosomal-dominant craniosynostosis syndrome characterized by unilateral or bilateral coronal craniosynostosis, hearing loss, intellectual disability, and relatively subtle limb findings such as carpal bone fusion and tarsal bone fusion. Muenke syndrome is caused by a single defining point mutation in the fibroblast growth factor receptor 3 (FGFR3) gene. Epilepsy rarely occurs in individuals with Muenke syndrome, and little detail is reported on types of epilepsy, patient characteristics, and long-term outcomes. We present seven patients with Muenke syndrome and seizures. A review of 789 published cases of Muenke syndrome, with a focus on epilepsy and intracranial anomalies in Muenke syndrome, revealed epilepsy in six patients, with intracranial anomalies in five. The occurrence of epilepsy in Muenke syndrome within our cohort of 58 patients, of whom seven manifested epilepsy, and the intracranial anomalies and epilepsy reported in the literature, suggest that patients with Muenke syndrome may be at risk for epilepsy and intracranial anomalies. Furthermore, the impact of Muenke syndrome on the central nervous system may be greater than previously thought.
Topics: Adult; Child; Child, Preschool; Craniosynostoses; Epilepsy; Humans; Infant; Receptor, Fibroblast Growth Factor, Type 3
PubMed: 23044018
DOI: 10.1016/j.pediatrneurol.2012.07.004 -
Developmental Dynamics : An Official... Nov 2011Muenke syndrome caused by the FGFR3(P250R) mutation is an autosomal dominant disorder mostly identified with coronal suture synostosis, but it also presents with other...
The Muenke syndrome mutation (FgfR3P244R) causes cranial base shortening associated with growth plate dysfunction and premature perichondrial ossification in murine basicranial synchondroses.
Muenke syndrome caused by the FGFR3(P250R) mutation is an autosomal dominant disorder mostly identified with coronal suture synostosis, but it also presents with other craniofacial phenotypes that include mild to moderate midface hypoplasia. The Muenke syndrome mutation is thought to dysregulate intramembranous ossification at the cranial suture without disturbing endochondral bone formation in the skull. We show in this study that knock-in mice harboring the mutation responsible for the Muenke syndrome (FgfR3(P244R)) display postnatal shortening of the cranial base along with synchondrosis growth plate dysfunction characterized by loss of resting, proliferating and hypertrophic chondrocyte zones and decreased Ihh expression. Furthermore, premature conversion of resting chondrocytes along the perichondrium into prehypertrophic chondrocytes leads to perichondrial bony bridge formation, effectively terminating the postnatal growth of the cranial base. Thus, we conclude that the Muenke syndrome mutation disturbs endochondral and perichondrial ossification in the cranial base, explaining the midface hypoplasia in patients.
Topics: Amino Acid Substitution; Animals; Arginine; Cranial Sutures; Craniosynostoses; Growth Plate; Mice; Mice, Transgenic; Models, Biological; Mutation, Missense; Ossification, Heterotopic; Osteogenesis; Phenotype; Proline; Receptor, Fibroblast Growth Factor, Type 3; Skull Base; X-Ray Microtomography
PubMed: 22016144
DOI: 10.1002/dvdy.22752 -
Bone Reports Jun 2022Faciocraniosynostoses (FCS) are malformations affecting the development of the bones of the skull and face, due to the premature closure of one or more craniofacial...
OBJECTIVE
Faciocraniosynostoses (FCS) are malformations affecting the development of the bones of the skull and face, due to the premature closure of one or more craniofacial sutures, mostly secondary to activating () 1-3 mutations. Gain-of-function mutations are also responsible for various conditions referred to as osteochondrodysplasia (OCD), characterized by structural and functional abnormalities of growth plate cartilages. We hypothesized that patients with -related faciocraniosynostoses may present extra-cranial growth anomalies.
STUDY DESIGN
We retrospectively collected height and weight data from a cohort of 70 patients. Included patients were admitted for -related FCS between 2000 and 2021 at the Craniofacial Unit of Necker - Enfants Malades University Hospital in Paris, France.
RESULTS
We showed that -related faciocraniosynostoses had significantly reduced heights and weights relative to controls, and that two specific time periods (1-3 years and > 8 years of age) were associated with lower height and weight values. Four patients had received growth hormone treatment but remained below normal values for growth in height and weight.
CONCLUSIONS
Patients with -related faciocraniosynostoses have clinically significant extra-cranial anomalies which are not currently investigated and managed in usual protocols; these patients could benefit from a systematic pre-pubertal endocrine assessment. More generally, our results extend the scope of extracranial anomalies in -related faciocraniosynostoses and support the hypothesis that all conditions with activating mutations affect both membranous ossification and long bones.
PubMed: 35372644
DOI: 10.1016/j.bonr.2022.101524 -
American Journal of Audiology Jun 2014There are a number of craniosynostosis syndromes with hearing loss-including Muenke, Apert, Pfeiffer, Crouzon, Beare-Stevenson, Crouzon with acanthosis nigricans, and... (Review)
Review
PURPOSE
There are a number of craniosynostosis syndromes with hearing loss-including Muenke, Apert, Pfeiffer, Crouzon, Beare-Stevenson, Crouzon with acanthosis nigricans, and Jackson-Weiss syndromes-that result from mutations in the fibroblast growth factor receptor (FGFR) genes. Studies of FGFRs and their ligands, fibroblast growth factors (FGFs), have revealed clues to the precise contribution of aberrant FGFR signaling to inner ear morphogenesis and the hearing loss encountered in craniosynostoses. The purpose of this article is to review basic studies of FGFRs with emphasis on their function and expression in the inner ear and surrounding structures.
METHOD
A Medline search was performed to find basic science articles regarding FGFR, their ligands, and their expression and relevant mouse models. Additional items searched included clinical descriptions and studies of individuals with FGFR-related craniosynostosis syndromes.
RESULTS
The FGF signaling pathway is essential for the morphogensis and proper function of the inner ear and auditory sensory epithelium.
CONCLUSION
The variable auditory phenotypes seen in individuals with Muenke syndrome may have a genetic basis, likely due to multiple interacting factors in the genetic environment or modifying factors. Further analysis and studies of mouse models of Muenke syndrome, in particular, may provide clues to the specific effects of the defining mutation in FGFR3 in the inner ear not only at birth but also into adulthood. In particular, investigations into these models may give insight into the variable expression and incomplete penetrance of this phenotype.
Topics: Animals; Child; Craniosynostoses; Deafness; Disease Models, Animal; Genetic Therapy; Hearing Loss; Humans; Mice; Receptor, Fibroblast Growth Factor, Type 3; Receptors, Fibroblast Growth Factor; Signal Transduction; Syndrome
PubMed: 24686979
DOI: 10.1044/2014_AJA-13-0036 -
Clinical Oral Investigations Jul 2019To determine whether the intramaxillary relationship of patients with Muenke syndrome and Saethre-Chotzen syndrome or TCF12-related craniosynostosis are systematically...
OBJECTIVES
To determine whether the intramaxillary relationship of patients with Muenke syndrome and Saethre-Chotzen syndrome or TCF12-related craniosynostosis are systematically different than those of a control group.
MATERIAL AND METHODS
Forty-eight patients (34 patients with Muenke syndrome, 8 patients with Saethre-Chotzen syndrome, and 6 patients with TCF12-related craniosynostosis) born between 1982 and 2010 (age range 4.84 to 16.83 years) that were treated at the Department of Oral Maxillofacial Surgery, Special Dental Care and Orthodontics, Children's Hospital Erasmus University Medical Center, Sophia, Rotterdam, the Netherlands, were included. Forty-seven syndromic patients had undergone one craniofacial surgery according to the craniofacial team protocol. The dental arch measurements intercanine width (ICW), intermolar width (IMW), arch depth (AD), and arch length (AL) were calculated. The control group existed of 329 nonsyndromic children.
RESULTS
All dental arch dimensions in Muenke (ICW, IMW, AL, p < 0.001, ADmax, p = 0.008; ADman, p = 0.002), Saethre-Chotzen syndrome, or TCF12-related craniosynostosis patients (ICWmax, p = 0.005; ICWman, IMWmax, AL, p < 0.001) were statistically significantly smaller than those of the control group.
CONCLUSIONS
In this study, we showed that the dental arches of the maxilla and the mandible of patients with Muenke syndrome and Saethre-Chotzen syndrome or TCF12-related craniosynostosis are smaller compared to those of a control group.
CLINICAL RELEVANCE
To gain better understanding of the sutural involvement in the midface and support treatment capabilities of medical and dental specialists in these patients, we suggest the concentration of patients with Muenke and Saethre-Chotzen syndromes or TCF12-related craniosynostosis in specialized teams for a multi-disciplinary approach and treatment.
Topics: Acrocephalosyndactylia; Adolescent; Child; Child, Preschool; Craniosynostoses; Dental Arch; Female; Humans; Male; Netherlands; Syndrome
PubMed: 30392078
DOI: 10.1007/s00784-018-2710-9 -
Journal of Developmental Biology Sep 2021In this case report, we focus on Muenke syndrome (MS), a disease caused by the p.Pro250Arg variant in fibroblast growth factor receptor 3 (FGFR3) and characterized by...
In this case report, we focus on Muenke syndrome (MS), a disease caused by the p.Pro250Arg variant in fibroblast growth factor receptor 3 (FGFR3) and characterized by uni- or bilateral coronal suture synostosis, macrocephaly without craniosynostosis, dysmorphic craniofacial features, and dental malocclusion. The clinical findings of MS are further complicated by variable expression of phenotypic traits and incomplete penetrance. As such, unraveling the mechanisms behind MS will require a comprehensive and systematic way of phenotyping patients to precisely identify the impact of the mutation variant on craniofacial development. To establish this framework, we quantitatively delineated the craniofacial phenotype of an individual with MS and compared this to his unaffected parents using three-dimensional cephalometric analysis of cone beam computed tomography scans and geometric morphometric analysis, in addition to an extensive clinical evaluation. Secondly, given the utility of human induced pluripotent stem cells (hiPSCs) as a patient-specific investigative tool, we also generated the first hiPSCs derived from a family trio, the proband and his unaffected parents as controls, with detailed characterization of all cell lines. This report provides a starting point for evaluating the mechanistic underpinning of the craniofacial development in MS with the goal of linking specific clinical manifestations to molecular insights gained from hiPSC-based disease modeling.
PubMed: 34698187
DOI: 10.3390/jdb9040039 -
Human Molecular Genetics Jan 2009The heterozygous Pro250Arg substitution mutation in fibroblast growth factor receptor 3 (FGFR3), which increases ligand-dependent signalling, is the most common genetic...
The heterozygous Pro250Arg substitution mutation in fibroblast growth factor receptor 3 (FGFR3), which increases ligand-dependent signalling, is the most common genetic cause of craniosynostosis in humans and defines Muenke syndrome. Since FGF signalling plays dosage-sensitive roles in the differentiation of the auditory sensory epithelium, we evaluated hearing in a large group of Muenke syndrome subjects, as well as in the corresponding mouse model (Fgfr3(P244R)). The Muenke syndrome cohort showed significant, but incompletely penetrant, predominantly low-frequency sensorineural hearing loss, and the Fgfr3(P244R) mice showed dominant, fully penetrant hearing loss that was more severe than that in Muenke syndrome individuals, but had the same pattern of relative high-frequency sparing. The mouse hearing loss correlated with an alteration in the fate of supporting cells (Deiters'-to-pillar cells) along the entire length of the cochlear duct, with the most extreme abnormalities found at the apical or low-frequency end. In addition, there was excess outer hair cell development in the apical region. We conclude that low-frequency sensorineural hearing loss is a characteristic feature of Muenke syndrome and that the genetically equivalent mouse provides an excellent model that could be useful in testing hearing loss therapies aimed at manipulating the levels of FGF signalling in the inner ear.
Topics: Amino Acid Substitution; Animals; Cohort Studies; Disease Models, Animal; Ear, Inner; Female; Hair Cells, Auditory; Hearing Loss; Hearing Tests; Humans; Male; Mice; Mice, Inbred Strains; Mice, Transgenic; Receptor, Fibroblast Growth Factor, Type 3; Signal Transduction
PubMed: 18818193
DOI: 10.1093/hmg/ddn311 -
Child's Nervous System : ChNS :... Sep 2012The Muenke syndrome mutation (FGFR3 (P250R)), which was discovered 15 years ago, represents the single most common craniosynostosis mutation. Muenke syndrome is...
PURPOSE
The Muenke syndrome mutation (FGFR3 (P250R)), which was discovered 15 years ago, represents the single most common craniosynostosis mutation. Muenke syndrome is characterized by coronal suture synostosis, midface hypoplasia, subtle limb anomalies, and hearing loss. However, the spectrum of clinical presentation continues to expand. To better understand the pathophysiology of the Muenke syndrome, we present collective findings from several recent studies that have characterized a genetically equivalent mouse model for Muenke syndrome (FgfR3 (P244R)) and compare them with human phenotypes.
CONCLUSIONS
FgfR3 (P244R) mutant mice show premature fusion of facial sutures, premaxillary and/or zygomatic sutures, but rarely the coronal suture. The mice also lack the typical limb phenotype. On the other hand, the mutant mice display maxillary retrusion in association with a shortening of the anterior cranial base and a premature closure of intersphenoidal and spheno-occipital synchondroses, resembling human midface hypoplasia. In addition, sensorineural hearing loss is detected in all FgfR3 (P244R) mutant mice as in the majority of Muenke syndrome patients. It is caused by a defect in the mechanism of cell fate determination in the organ of Corti. The mice also express phenotypes that have not been previously described in humans, such as reduced cortical bone thickness, hypoplastic trabecular bone, and defective temporomandibular joint structure. Therefore, the FgfR3 (P244R) mouse provides an excellent opportunity to study disease mechanisms of some classical phenotypes of Muenke syndrome and to test novel therapeutic strategies. The mouse model can also be further explored to discover previously unreported yet potentially significant phenotypes of Muenke syndrome.
Topics: Animals; Bone Diseases, Developmental; Cranial Sutures; Craniosynostoses; Disease Models, Animal; Female; Hearing Loss, Sensorineural; Humans; Imaging, Three-Dimensional; Infant; Male; Mice; Models, Biological; Mutation; Phenotype; Receptor, Fibroblast Growth Factor, Type 3; Temporomandibular Joint; Tomography, X-Ray Computed
PubMed: 22872265
DOI: 10.1007/s00381-012-1778-9 -
Genes & Development Nov 2013The stereotyped arrangement of cochlear sensory and supporting cells is critical for auditory function. Our previous studies showed that Muenke syndrome model mice...
The stereotyped arrangement of cochlear sensory and supporting cells is critical for auditory function. Our previous studies showed that Muenke syndrome model mice (Fgfr3P244R/+) have hearing loss associated with a supporting cell fate transformation of two Deiters' cells to two pillar cells. We investigated the developmental origins of this transformation and found that two prospective Deiters' cells switch to an outer pillar cell-like fate sequentially between embryonic day 17.5 (E17.5) and postnatal day 3 (P3). Unexpectedly, the Fgfr3P244R/+ hearing loss and supporting cell fate transformation are not rescued by genetically reducing fibroblast growth factor 8 (FGF8), the FGF receptor 3c (FGFR3c) ligand required for pillar cell differentiation. Rather, reducing FGF10, which normally activates FGFR2b or FGFR1b, is sufficient for rescue of cochlear form and function. Accordingly, we found that the P244R mutation changes the specificity of FGFR3b and FGFR3c such that both acquire responsiveness to FGF10. Moreover, Fgf10 heterozygosity does not block the Fgfr3P244R/+ supporting cell fate transformation but instead allows a gradual reversion of fate-switched cells toward the normal phenotype between P5 and at least P14. This study indicates that Deiters' and pillar cells can reversibly switch fates in an FGF-dependent manner over a prolonged period of time. This property might be exploited for the regulation of sensory cell regeneration from support cells.
Topics: Animals; Cell Differentiation; Cochlea; Craniosynostoses; Disease Models, Animal; Fibroblast Growth Factors; Gene Dosage; Hair Cells, Auditory; Hearing Loss; Mice; Signal Transduction
PubMed: 24145799
DOI: 10.1101/gad.228957.113 -
Journal of Dental Research Jul 2012Muenke syndrome is characterized by various craniofacial deformities and is caused by an autosomal-dominant activating mutation in fibroblast growth factor receptor 3...
Muenke syndrome is characterized by various craniofacial deformities and is caused by an autosomal-dominant activating mutation in fibroblast growth factor receptor 3 (FGFR3(P250R) ). Here, using mice carrying a corresponding mutation (FgfR3(P244R) ), we determined whether the mutation affects temporomandibular joint (TMJ) development and growth. In situ hybridization showed that FgfR3 was expressed in condylar chondroprogenitors and maturing chondrocytes that also expressed the Indian hedgehog (Ihh) receptor and transcriptional target Patched 1(Ptch1). In FgfR3(P244R) mutants, the condyles displayed reduced levels of Ihh expression, H4C-positive proliferating chondroprogenitors, and collagen type II- and type X-expressing chondrocytes. Primary bone spongiosa formation was also disturbed and was accompanied by increased osteoclastic activity and reduced trabecular bone formation. Treatment of wild-type condylar explants with recombinant FGF2/FGF9 decreased Ptch1 and PTHrP expression in superficial/polymorphic layers and proliferation in chondroprogenitors. We also observed early degenerative changes of condylar articular cartilage, abnormal development of the articular eminence/glenoid fossa in the TMJ, and fusion of the articular disc. Analysis of our data indicates that the activating FgfR3(P244R) mutation disturbs TMJ developmental processes, likely by reducing hedgehog signaling and endochondral ossification. We suggest that a balance between FGF and hedgehog signaling pathways is critical for the integrity of TMJ development and for the maintenance of cellular organization.
Topics: Animals; Cartilage, Articular; Chondrogenesis; Craniosynostoses; Fibroblast Growth Factors; Gene Knock-In Techniques; Hedgehog Proteins; Mandibular Condyle; Mice; Mice, Mutant Strains; Mutation; Osteogenesis; Receptor, Fibroblast Growth Factor, Type 3; Signal Transduction; Temporal Bone; Temporomandibular Joint
PubMed: 22622662
DOI: 10.1177/0022034512449170