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Bendon CL, Fenwick AL, Hurst JA, Nürnberg G, Nürnberg P, Wall SA, Wilkie AOM, Johnson D. Frank-ter Haar syndrome associated with sagittal craniosynostosis and raised intracranial pressure. BMC MEDICAL GENETICS 2012; 13:104. [PMID: 23140272 PMCID: PMC3532175 DOI: 10.1186/1471-2350-13-104] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2012] [Accepted: 10/29/2012] [Indexed: 11/10/2022]
Abstract
BACKGROUND Frank-ter Haar syndrome is a rare disorder associated with skeletal, cardiac, ocular and craniofacial features including hypertelorism and brachycephaly. The most common underlying genetic defect in Frank-ter Haar syndrome appears to be a mutation in the SH3PXD2B gene on chromosome 5q35.1. Craniosynostosis, or premature fusion of the calvarial sutures, has not previously been described in Frank-ter Haar syndrome. CASE PRESENTATION We present a family of three affected siblings born to consanguineous parents with clinical features in keeping with a diagnosis of Frank-ter Haar syndrome. All three siblings have a novel mutation caused by the deletion of exon 13 of the SH3PXD2B gene. Two of the three siblings also have non-scaphocephalic sagittal synostosis associated with raised intracranial pressure. CONCLUSION The clinical features of craniosynostosis and raised intracranial pressure in this family with a confirmed diagnosis of Frank-ter Haar syndrome expand the clinical spectrum of the disease. The abnormal cranial proportions in a mouse model of the disease suggests that the association is not coincidental. The possibility of craniosynostosis should be considered in individuals with a suspected diagnosis of Frank-ter Haar syndrome.
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Affiliation(s)
- Charlotte L Bendon
- Oxford Craniofacial Unit, Oxford University Hospitals NHS Trust, John Radcliffe Hospital, Oxford OX3 9DU, UK
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202
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Gómez-Valdés JA, Hünemeier T, Contini V, Acuña-Alonzo V, Macin G, Ballesteros-Romero M, Corral P, Ruiz-Linares A, Sánchez-Mejorada G, Canizales-Quinteros S, Martínez-Abadías N, Salzano FM, González-José R, Bortolini MC. Fibroblast growth factor receptor 1 (FGFR1) variants and craniofacial variation in Amerindians and related populations. Am J Hum Biol 2012; 25:12-9. [PMID: 23070782 DOI: 10.1002/ajhb.22331] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 08/17/2012] [Accepted: 09/10/2012] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVES The polymorphic site rs4647905 of the FGFR1 gene was previously associated with a decrease in cephalic index (CI). Here, we evaluate the relationships between genotypes and cephalometric measurements and indices in one Mexican Native and two mestizo Mexican populations using two haplotype-tag SNPs (rs4647905 and rs3213849) that represent >85% of the FGFR1 variability, plus three other SNPs (rs2293971, rs2304000, and rs930828) situated nearby. In addition, we genotyped five South American natives, two European, one African, and one Siberian populations to evaluate their intra and intercontinental population diversity. METHODS The five SNPs were tested and the craniofacial measurements and indices were collected using standardized procedures. Principal Component Analysis was used to verify individual/population comparisons. Associations were performed through the generalized linear model (GLM), coefficient of determination R(2) and linear regression tests. RESULTS We found a tendency for a decrease in CI in individuals homozygous for allele rs4647905C, regardless of the population to which they belong, though the effect is more pronounced in mestizo. When the GLM analyses were performed using the absolute/linear cephalometric measurements, a statistically significant association was found between four SNPs and head length in the mestizo population. CONCLUSIONS FGFR1 polymorphisms, especially rs4647905, can have an important role in the normal human skull variation, primarily due to their influence in head length, which would affect other cephalometric absolute/linear measures as well as indices like CI as a result of the pervasive nature of the morphological integration that characterizes the human skull.
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Affiliation(s)
- Jorge A Gómez-Valdés
- Laboratorio de Antropología Física, Departamento de Anatomía, Faculta de Medicina, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
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Senarath-Yapa K, Chung MT, McArdle A, Wong VW, Quarto N, Longaker MT, Wan DC. Craniosynostosis: molecular pathways and future pharmacologic therapy. Organogenesis 2012; 8:103-13. [PMID: 23249483 DOI: 10.4161/org.23307] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Craniosynostosis describes the premature fusion of one or more cranial sutures and can lead to dramatic manifestations in terms of appearance and functional impairment. Contemporary approaches for this condition are primarily surgical and are associated with considerable morbidity and mortality. The additional post-operative problems of suture refusion and bony relapse may also necessitate repeated surgeries with their own attendant risks. Therefore, a need exists to not only optimize current strategies but also to develop novel biological therapies which could obviate the need for surgery and potentially treat or even prevent premature suture fusion. Clinical studies of patients with syndromic craniosynostosis have provided some useful insights into the important signaling pathways and molecular events guiding suture fate. Furthermore, the highly conserved nature of craniofacial development between humans and other species have permitted more focused and step-wise elucidation of the molecular underpinnings of craniosynostosis. This review will describe the clinical manifestations of craniosynostosis, reflect on our understanding of syndromic and non-syndromic craniosynostoses and outline the different approaches that have been adopted in our laboratory and elsewhere to better understand the pathogenesis of premature suture fusion. Finally, we will assess to what extent our improved understanding of the pathogenesis of craniosynostosis, achieved through laboratory-based and clinical studies, have made the possibility of a non-surgical pharmacological approach both realistic and tangible.
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Affiliation(s)
- Kshemendra Senarath-Yapa
- Hagey Laboratory for Pediatric Regenerative Medicine; Department of Surgery; Stanford University School of Medicine; Stanford, CA USA
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Hermann CD, Lee CSD, Gadepalli S, Lawrence KA, Richards MA, Olivares-Navarrete R, Williams JK, Schwartz Z, Boyan BD. Interrelationship of cranial suture fusion, basicranial development, and resynostosis following suturectomy in twist1(+/-) mice, a murine model of Saethre-Chotzen syndrome. Calcif Tissue Int 2012; 91:255-66. [PMID: 22903506 DOI: 10.1007/s00223-012-9632-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 06/07/2012] [Indexed: 01/12/2023]
Abstract
The interrelationships among suture fusion, basicranial development, and subsequent resynostosis in syndromic craniosynostosis have yet to be examined. The objectives of this study were to determine the potential relationship between suture fusion and cranial base development in a model of syndromic craniosynostosis and to assess the effects of the syndrome on resynostosis following suturectomy. To do this, posterior frontal and coronal suture fusion, postnatal development of sphenooccipital synchondrosis, and resynostosis in Twist1(+/+) (WT) and Twist1(+/-) litter-matched mice (a model for Saethre-Chotzen syndrome) were quantified by evaluating μCT images with advanced image-processing algorithms. The coronal suture in Twist(+/-) mice developed, fused, and mineralized at a faster rate than that in normal littermates at postnatal days 6-30. Moreover, premature fusion of the coronal suture in Twist1(+/-) mice preceded alterations in cranial base development. Analysis of synchondrosis showed faster mineralization in Twist(+/-) mice at postnatal days 25-30. In a rapid resynostosis model, there was an inability to fuse both the midline posterior frontal suture and craniotomy defects in 21-day-old Twist(+/-) mice, despite having accelerated mineralization in the posterior frontal suture and defects. This study showed that dissimilarities between Twist1(+/+) and Twist1(+/-) mice are not limited to a fused coronal suture but include differences in fusion of other sutures, the regenerative capacity of the cranial vault, and the development of the cranial base.
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Affiliation(s)
- Christopher D Hermann
- Wallace H. Coulter Department of Biomedical Engineering, Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332-0363, USA
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Nah HD, Koyama E, Agochukwu NB, Bartlett SP, Muenke M. Phenotype profile of a genetic mouse model for Muenke syndrome. Childs Nerv Syst 2012; 28:1483-93. [PMID: 22872265 PMCID: PMC4131982 DOI: 10.1007/s00381-012-1778-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 04/13/2012] [Indexed: 10/28/2022]
Abstract
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.
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Affiliation(s)
- Hyun-Duck Nah
- Plastic and Reconstructive Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
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Bernardini C, Barba M, Tamburrini G, Massimi L, Di Rocco C, Michetti F, Lattanzi W. Gene expression profiling in human craniosynostoses: a tool to investigate the molecular basis of suture ossification. Childs Nerv Syst 2012; 28:1295-300. [PMID: 22872240 DOI: 10.1007/s00381-012-1780-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Accepted: 04/16/2012] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Non-syndromic craniosynostoses (NSC) occur as isolated skull malformations due to the premature ossification of one (single-suture forms) or more (complex forms) calvarial sutures and represent the most frequent form of craniosynostosis worldwide. The etiology of NSC is still largely unknown as a genetic basis can be rarely demonstrated especially in single-suture forms. In these cases, during the prenatal/perinatal development of affected patients, only one suture undergoes a premature direct ossification within an otherwise physiologically grown skull. This could suggest that definite somatic alterations, possibly due to unclear environmental agents, occur locally at the site of premature suture fusion during skull development. A promising tool to investigate the molecular mechanisms that may orchestrate this event is the comparative analysis of suture- and synostosis-derived tissues and cells. PURPOSE This review focuses on the different studies that attempted to clarify this issue using genome-wide microarray-based technologies for the comparative analysis of gene expression profiles. All relevant results have been comprehensively reviewed, possibly compared, and critically discussed. CONCLUSION Due to the heterogeneity of the dataset available in the literature, a univocal CRS-associated molecular profile could not be deciphered. Most differentially expressed genes are found in different studies to be involved in extracellular matrix remodeling.
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Affiliation(s)
- Camilla Bernardini
- Institute of Anatomy and Cell Biology, Università Cattolica del Sacro Cuore, Largo F. Vito, 1, 00168, Rome, Italy
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Cray JJ, Burrows AM, Vecchione L, Kinsella CR, Losee JE, Moursi AM, Siegel MI, Cooper GM, Mooney MP. Relaxin Does Not Rescue Coronal Suture Fusion in Craniosynostotic Rabbits. Cleft Palate Craniofac J 2012; 49:e46-54. [DOI: 10.1597/11-024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Objectives Craniosynostosis affects 1 in 2000 to 3000 live births and may result in craniofacial and neural growth disturbances. Histological data have shown that thick collagenous bundles are present in the sutural ligament, which may tether the osteogenic fronts, resulting in premature fusion. The hormone relaxin has been shown to disrupt collagen fiber organization, possibly preventing craniosynostosis by relaxing the sutural ligament and allowing osteogenic fronts to separate normally and stay patent. This study tested this hypothesis with a rabbit model of delayed-onset coronal suture synostosis. Methods A total of 18 New Zealand White rabbits with craniosynostosis were randomly assigned to one of three groups: sham control, protein control (BSA), relaxin treatment. After initial diagnosis, sham surgery, BSA, or relaxin was delivered to the fusing coronal suture in a slow-release (56-day) collagen vehicle. Longitudinal radiographs and body weights were collected at 10, 25, 42, and 84 days of age, and sutures were harvested for histology. Results Relaxin-treated animals had more disorganized intrasuture content than control groups. These specimens also appeared to have relatively wider sutures ectocranially. There were no significant differences in relaxin-treated animals for all craniofacial growth measures, or suture separation compared with controls. Conclusions These data do not support our initial hypothesis that the use of relaxin may rescue sutures destined to undergo premature suture fusion. These findings suggest that collagen fiber arrangement may not be important for suture fusion. This protein therapy would not be clinically useful for craniosynostosis.
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Affiliation(s)
- James J. Cray
- Department of Surgery, Division of Plastic Surgery, Pediatric Craniofacial Biology Laboratory, Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Anne M. Burrows
- Department of Physical Therapy, Duquesne University, Pittsburgh, Pennsylvania, and Department of Anthropology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Lisa Vecchione
- Pittsburgh Cleft–Craniofacial Research Center, Pittsburgh, Pennsylvania, and Assistant Clinical Professor of Surgery, Department of Surgery, Division of Plastic Surgery and Department of Orthodontics and Dentofacial Orthopedics, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Christopher R. Kinsella
- Department of Surgery, Division of Plastic Surgery, Pediatric Craniofacial Biology Laboratory, Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Joseph E. Losee
- Surgery and Pediatrics, Chief, Pediatric Plastic Surgery, and Director, Pittsburgh Cleft–Craniofacial Center Program, Pittsburgh, Pennslyvania, and Plastic Surgery Residency, Department of Surgery, Division of Plastic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Amr M. Moursi
- Department of Pediatric Dentistry, New York University, New York, New York
| | - Michael I. Siegel
- Departments of Anthropology and Orthodontics, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Gregory M. Cooper
- Department of Surgery, Division of Plastic Surgery, Department of Orthopedic Surgery, and Department of Oral Biology, and Children's Hospital of Pittsburgh University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Mark P. Mooney
- Departments of Anthropology, Surgery–Division of Plastic Surgery, and Orthodontics
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Agochukwu NB, Solomon BD, Muenke M. Impact of genetics on the diagnosis and clinical management of syndromic craniosynostoses. Childs Nerv Syst 2012; 28:1447-63. [PMID: 22872262 PMCID: PMC4101189 DOI: 10.1007/s00381-012-1756-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 03/29/2012] [Indexed: 10/28/2022]
Abstract
PURPOSE More than 60 different mutations have been identified to be causal in syndromic forms of craniosynostosis. The majority of these mutations occur in the fibroblast growth factor receptor 2 gene (FGFR2). The clinical management of syndromic craniosynostosis varies based on the particular causal mutation. Additionally, the diagnosis of a patient with syndromic craniosynostosis is based on the clinical presentation, signs, and symptoms. The understanding of the hallmark features of particular syndromic forms of craniosynostosis leads to efficient diagnosis, management, and long-term prognosis of patients with syndromic craniosynostoses. METHODS A comprehensive literature review was done with respect to the major forms of syndromic craniosynostosis and additional less common FGFR-related forms of syndromic craniosynostosis. Additionally, information and data gathered from studies performed in our own investigative lab (lab of Dr. Muenke) were further analyzed and reviewed. A literature review was also performed with regard to the genetic workup and diagnosis of patients with craniosynostosis. RESULTS Patients with Apert syndrome (craniosynostosis syndrome due to mutations in FGFR2) are most severely affected in terms of intellectual disability, developmental delay, central nervous system anomalies, and limb anomalies. All patients with FGFR-related syndromic craniosynostosis have some degree of hearing loss that requires thorough initial evaluations and subsequent follow-up. CONCLUSIONS Patients with syndromic craniosynostosis require management and treatment of issues involving multiple organ systems which span beyond craniosynostosis. Thus, effective care of these patients requires a multidisciplinary approach.
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Affiliation(s)
- Nneamaka B Agochukwu
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, NIH, MSC 3717, Building 35, Room 1B-207, Bethesda, MD 20892, USA
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Abstract
PURPOSE This study aimed to review and discuss the utility of the Fgfr2 (W290R) mouse mutant as a model of human Crouzon syndrome. METHODS A review of current and past scientific literature on Fibroblast Growth Factor Receptor-2 (FGFR2) protein domain structure, FGFR mutations associated with human Crouzon syndrome, and phenotypic and molecular changes combined with recent observations and experimental data of the Fgfr2 (W290R) mouse mutant was conducted. A comparison of the Fgfr2 (W290R) mouse mutant with another mouse model of Crouzon syndrome, Fgfr2 (C342R) mouse mutant, was also performed. Finally, possible future research directions using the Fgfr2 (W290R) mutant mice were discussed. RESULTS The Fgfr2 (W290R) heterozygous mouse exhibits defects characteristic of human Crouzon syndrome. At the molecular level, the defects observed in the mouse mutant are due to the dysregulation of signaling of both the IIIb and IIIc isoforms of Fgfr2. The involvement of the IIIb isoform of FGFR2 in the etiopathology of Crouzon syndrome is a novel finding in the craniosynostosis literature field. Dysregulated signaling of both IIIb and IIIc isoforms causes a broad spectrum of changes that explain some of the defects observed clinically in humans. Several of the defects observed in the Fgfr2 (W290R) homozygous mouse mutant are attributable to a loss-of-function mechanism in contrast to the frequently reported gain-of-function receptor function associated with mutated FGF receptors in craniosynostosis. CONCLUSIONS The Fgfr2 ( W290R ) mouse model can be used as a model system to further investigate the cellular, molecular, and biochemical mechanisms of Crouzon syndrome.
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210
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The role of vertebrate models in understanding craniosynostosis. Childs Nerv Syst 2012; 28:1471-81. [PMID: 22872264 DOI: 10.1007/s00381-012-1844-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Accepted: 06/13/2012] [Indexed: 01/10/2023]
Abstract
BACKGROUND Craniosynostosis (CS), the premature fusion of cranial sutures, is a relatively common pediatric anomaly, occurring in isolation or as part of a syndrome. A growing number of genes with pathologic mutations have been identified for syndromic and nonsyndromic CS. The study of human sutural material obtained post-operatively is not sufficient to understand the etiology of CS, for which animal models are indispensable. DISCUSSION The similarity of the human and murine calvarial structure, our knowledge of mouse genetics and biology, and ability to manipulate the mouse genome make the mouse the most valuable model organism for CS research. A variety of mouse mutants are available that model specific human CS mutations or have CS phenotypes. These allow characterization of the biochemical and morphological events, often embryonic, which precede suture fusion. Other vertebrate organisms have less functional genetic utility than mice, but the rat, rabbit, chick, zebrafish, and frog provide alternative systems in which to validate or contrast molecular functions relevant to CS.
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211
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Heuzé Y, Martínez-Abadías N, Stella JM, Senders CW, Boyadjiev SA, Lo LJ, Richtsmeier JT. Unilateral and bilateral expression of a quantitative trait: asymmetry and symmetry in coronal craniosynostosis. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2012; 318:109-22. [PMID: 22532473 DOI: 10.1002/jezb.21449] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Bilateral symmetry in vertebrates is imperfect and mild asymmetries are found in normal growth and development. However, abnormal development is often characterized by strong asymmetries. Coronal craniosynostosis, defined here as consisting of premature suture closure and a characteristic skull shape, is a complex trait. The premature fusion of the coronal suture can occur unilaterally associated with skull asymmetry (anterior plagiocephaly) or bilaterally associated with a symmetric but brachycephalic skull. We investigated the relationship between coronal craniosynostosis and skull bilateral symmetry. Three-dimensional landmark coordinates were recorded on preoperative computed tomography images of children diagnosed with coronal nonsyndromic craniosynostosis (N = 40) and that of unaffected individuals (N = 20) and analyzed by geometric morphometrics. Our results showed that the fusion pattern of the coronal suture is similar across individuals and types of coronal craniosynostosis. Shape analysis showed that skulls of bilateral coronal craniosynostosis (BCS) and unaffected individuals display low degrees of asymmetry, whereas right and left unilateral coronal craniosynostosis (UCS) skulls are asymmetric and mirror images of one another. When premature fusion of the coronal suture (without taking into account cranial dysmorphology) is scored as a qualitative trait, the expected relationship between trait frequency and trait unilateral expression (i.e. negative correlation) is confirmed. Overall, we interpret our results as evidence that the same biological processes operate on the two sides in BCS skulls and on the affected side in UCS skulls, and that coronal craniosynostosis is a quantitative trait exhibiting a phenotypic continuum with BCS displaying more intense shape changes than UCS.
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Affiliation(s)
- Yann Heuzé
- Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania, USA
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212
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Dwivedi PP, Anderson PJ, Powell BC. Development of an efficient, non-viral transfection method for studying gene function and bone growth in human primary cranial suture mesenchymal cells reveals that the cells respond to BMP2 and BMP3. BMC Biotechnol 2012; 12:45. [PMID: 22857382 PMCID: PMC3431223 DOI: 10.1186/1472-6750-12-45] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 07/25/2012] [Indexed: 01/05/2023] Open
Abstract
Background Achieving efficient introduction of plasmid DNA into primary cultures of mammalian cells is a common problem in biomedical research. Human primary cranial suture cells are derived from the connective mesenchymal tissue between the bone forming regions at the edges of the calvarial plates of the skull. Typically they are referred to as suture mesenchymal cells and are a heterogeneous population responsible for driving the rapid skull growth that occurs in utero and postnatally. To better understand the molecular mechanisms involved in skull growth, and in abnormal growth conditions, such as craniosynostosis, caused by premature bony fusion, it is essential to be able to easily introduce genes into primary bone forming cells to study their function. Results A comparison of several lipid-based techniques with two electroporation-based techniques demonstrated that the electroporation method known as nucleofection produced the best transfection efficiency. The parameters of nucleofection, including cell number, amount of DNA and nucleofection program, were optimized for transfection efficiency and cell survival. Two different genes and two promoter reporter vectors were used to validate the nucleofection method and the responses of human primary suture mesenchymal cells by fluorescence microscopy, RT-PCR and the dual luciferase assay. Quantification of bone morphogenetic protein (BMP) signalling using luciferase reporters demonstrated robust responses of the cells to both osteogenic BMP2 and to the anti-osteogenic BMP3. Conclusions A nucleofection protocol has been developed that provides a simple and efficient, non-viral alternative method for in vitro studies of gene and protein function in human skull growth. Human primary suture mesenchymal cells exhibit robust responses to BMP2 and BMP3, and thus nucleofection can be a valuable method for studying the potential competing action of these two bone growth factors in a model system of cranial bone growth.
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Affiliation(s)
- Prem P Dwivedi
- Craniofacial Research Group, Women's and Children's Health Research Institute, 72 King William Road, North Adelaide, South Australia 5006, Australia
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Thompson H, Ohazama A, Sharpe PT, Tucker AS. The origin of the stapes and relationship to the otic capsule and oval window. Dev Dyn 2012; 241:1396-404. [PMID: 22778034 DOI: 10.1002/dvdy.23831] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2012] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND The stapes, an ossicle found within the middle ear, is involved in transmitting sound waves to the inner ear by means of the oval window. There are several developmental problems associated with this ossicle and the oval window, which cause hearing loss. The developmental origin of these tissues has not been fully elucidated. RESULTS Using transgenic reporter mice, we have shown that the stapes is of dual origin with the stapedial footplate being composed of cells of both neural crest and mesodermal origin. Wnt1cre/Dicer mice fail to develop neural crest-derived cartilages, therefore, have no middle ear ossicles. We have shown in these mice the mesodermal stapedial footplate fails to form and the oval window is induced but underdeveloped. CONCLUSIONS If the neural crest part of the stapes fails to form the mesodermal part does not develop, indicating that the two parts are interdependent. The stapes develops tightly associated with the otic capsule, however, it is not essential for the positioning of the oval window, suggesting that other tissues, perhaps within the inner ear are needed for oval window placement.
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Affiliation(s)
- Hannah Thompson
- Department of Craniofacial Development and Stem Cell Biology, Kings College London, Guy's Tower, Guy's Hospital, London Bridge, London, UK
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Hershey T, Lugar HM, Shimony JS, Rutlin J, Koller JM, Perantie DC, Paciorkowski AR, Eisenstein SA, Permutt MA. Early brain vulnerability in Wolfram syndrome. PLoS One 2012; 7:e40604. [PMID: 22792385 PMCID: PMC3394712 DOI: 10.1371/journal.pone.0040604] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 06/11/2012] [Indexed: 12/30/2022] Open
Abstract
Wolfram Syndrome (WFS) is a rare autosomal recessive disease characterized by insulin-dependent diabetes mellitus, optic nerve atrophy, diabetes insipidus, deafness, and neurological dysfunction leading to death in mid-adulthood. WFS is caused by mutations in the WFS1 gene, which lead to endoplasmic reticulum (ER) stress-mediated cell death. Case studies have found widespread brain atrophy in late stage WFS. However, it is not known when in the disease course these brain abnormalities arise, and whether there is differential vulnerability across brain regions and tissue classes. To address this limitation, we quantified regional brain abnormalities across multiple imaging modalities in a cohort of young patients in relatively early stages of WFS. Children and young adults with WFS were evaluated with neurological, cognitive and structural magnetic resonance imaging measures. Compared to normative data, the WFS group had intact cognition, significant anxiety and depression, and gait abnormalities. Compared to healthy and type 1 diabetic control groups, the WFS group had smaller intracranial volume and preferentially affected gray matter volume and white matter microstructural integrity in the brainstem, cerebellum and optic radiations. Abnormalities were detected in even the youngest patients with mildest symptoms, and some measures did not follow the typical age-dependent developmental trajectory. These results establish that WFS is associated with smaller intracranial volume with specific abnormalities in the brainstem and cerebellum, even at the earliest stage of clinical symptoms. This pattern of abnormalities suggests that WFS has a pronounced impact on early brain development in addition to later neurodegenerative effects, representing a significant new insight into the WFS disease process. Longitudinal studies will be critical for confirming and expanding our understanding of the impact of ER stress dysregulation on brain development.
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Affiliation(s)
- Tamara Hershey
- Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri, United States of America.
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Holmes G, Basilico C. Mesodermal expression of Fgfr2S252W is necessary and sufficient to induce craniosynostosis in a mouse model of Apert syndrome. Dev Biol 2012; 368:283-93. [PMID: 22664175 DOI: 10.1016/j.ydbio.2012.05.026] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 04/19/2012] [Accepted: 05/22/2012] [Indexed: 10/28/2022]
Abstract
Coordinated growth of the skull and brain are vital to normal human development. Craniosynostosis, the premature fusion of the calvarial bones of the skull, is a relatively common pediatric disease, occurring in 1 in 2500 births, and requires significant surgical management, especially in syndromic cases. Syndromic craniosynostosis is caused by a variety of genetic lesions, most commonly by activating mutations of FGFRs 1-3, and inactivating mutations of TWIST1. In a mouse model of TWIST1 haploinsufficiency, cell mixing between the neural crest-derived frontal bone and mesoderm-derived parietal bone accompanies coronal suture fusion during embryonic development. However, the relevance of lineage mixing in craniosynostosis induced by activating FGFR mutations is unknown. Here, we demonstrate a novel mechanism of suture fusion in the Apert Fgfr2(S252W) mouse model. Using Cre/lox recombination we simultaneously induce expression of Fgfr2(S252W) and β-galactosidase in either the neural crest or mesoderm of the skull. We show that mutation of the mesoderm alone is necessary and sufficient to cause craniosynostosis, while mutation of the neural crest is neither. The lineage border is not disrupted by aberrant cell migration during fusion. Instead, the suture mesenchyme itself remains intact and is induced to undergo osteogenesis. We eliminate postulated roles for dura mater or skull base changes in craniosynostosis. The viability of conditionally mutant mice also allows post-natal assessment of other aspects of Apert syndrome.
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Affiliation(s)
- Greg Holmes
- Department of Microbiology, New York University School of Medicine, 550 1st Ave, New York, NY 10016, USA.
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216
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Deckelbaum RA, Holmes G, Zhao Z, Tong C, Basilico C, Loomis CA. Regulation of cranial morphogenesis and cell fate at the neural crest-mesoderm boundary by engrailed 1. Development 2012; 139:1346-58. [PMID: 22395741 DOI: 10.1242/dev.076729] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The characterization of mesenchymal progenitors is central to understanding development, postnatal pathology and evolutionary adaptability. The precise identity of the mesenchymal precursors that generate the coronal suture, an important structural boundary in mammalian skull development, remains unclear. We show in mouse that coronal suture progenitors originate from hedgehog-responsive cephalic paraxial mesoderm (Mes) cells, which migrate rapidly to a supraorbital domain and establish a unidirectional lineage boundary with neural crest (NeuC) mesenchyme. Lineage tracing reveals clonal and stereotypical expansion of supraorbital mesenchymal cells to form the coronal suture between E11.0 and E13.5. We identify engrailed 1 (En1) as a necessary regulator of cell movement and NeuC/Mes lineage boundary positioning during coronal suture formation. In addition, we provide genetic evidence that En1 functions upstream of fibroblast growth factor receptor 2 (Fgfr2) in regulating early calvarial osteogenic differentiation, and postulate that it plays an additional role in precluding premature osteogenic conversion of the sutural mesenchyme.
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Affiliation(s)
- Ron A Deckelbaum
- Department of Pathology, New York University School of Medicine, 550 1st Avenue, New York, NY 10016, USA.
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217
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Werneburg I, Tzika AC, Hautier L, Asher RJ, Milinkovitch MC, Sánchez-Villagra MR. Development and embryonic staging in non-model organisms: the case of an afrotherian mammal. J Anat 2012; 222:2-18. [PMID: 22537021 DOI: 10.1111/j.1469-7580.2012.01509.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Studies of evolutionary developmental biology commonly use 'model organisms' such as fruit flies or mice, and questions are often functional or epigenetic. Phylogenetic investigations, in contrast, typically use species that are less common and mostly deal with broad scale analyses in the tree of life. However, important evolutionary transformations have taken place at all taxonomic levels, resulting in such diverse forms as elephants and shrews. To understand the mechanisms underlying morphological diversification, broader sampling and comparative approaches are paramount. Using a simple, standardized protocol, we describe for the first time the development of soft tissues and some parts of the skeleton, using μCT-imaging of developmental series of Echinops telfairi and Tenrec ecaudatus, two tenrecid afrotherian mammals. The developmental timing of soft tissue and skeletal characters described for the tenrecids is briefly compared with that of other mammals, including mouse, echidna, and the opossum. We found relatively few heterochronic differences in development in the armadillo vs. tenrec, consistent with a close relationship of Xenarthra and Afrotheria. Ossification in T. ecaudatus continues well into the second half of overall gestation, resembling the pattern seen in other small mammals and differing markedly from the advanced state of ossification evident early in the gestation of elephants, sheep, and humans.
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Affiliation(s)
- Ingmar Werneburg
- Paläontologisches Institut und Museum, Universität Zürich, Zürich, Switzerland
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218
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The cell of origin of cranial Ewing's sarcoma: the dilemma persists. Acta Neurochir (Wien) 2012. [DOI: 10.1007/s00701-011-1263-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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219
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Sim SY, Yoon SH, Kim SY. Quantitative analysis of developmental process of cranial suture in korean infants. J Korean Neurosurg Soc 2012; 51:31-6. [PMID: 22396840 PMCID: PMC3291703 DOI: 10.3340/jkns.2012.51.1.31] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 01/05/2012] [Accepted: 01/25/2012] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE The purpose of this study was to elucidate the anatomical development of physiologic suture closure processes in infants using three dimensional reconstructed computed tomography (CT). METHODS A consecutive series of 243 infants under 12 months of age who underwent three dimensional CT were included in this study. Four major cranial sutures (sagittal, coronal, lambdoidal and metopic suture) were classified into four suture closure grades (grade 0=no closure along the whole length, grade 1=partial or intermittent closure, grade 2=complete closure with visible suture line, grade 3=complete fusion (ossification) without visible suture line), and measured for its closure degree (suture closure rates; defined as percentage of the length of closed suture line divided by the total length of suture line). RESULTS Suture closure grade under 12 months of age comprised of grade 0 (n=195, 80.2%), grade 1 (n=24, 9.9%) and grade 2 (n=24, 9.9%) in sagittal sutures, whereas in metopic sutures they were grade 0 (n=61, 25.1%), grade 1 (n=167, 68.7%), grade 2 (n=6, 24%) and grade 3 (n=9, 3.7%). Mean suture closure rates under 12 months of age was 58.8% in metopic sutures, followed by coronal (right : 43.8%, left : 41.1%), lambdoidal (right : 27.2%, left : 25.6%) and sagittal sutures (15.6%), respectively. CONCLUSION These quantitative descriptions of cranial suture closure may help understand the process involved in the cranial development of Korean infants.
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Affiliation(s)
- Sook Young Sim
- Department of Neurosurgery, National Medical Center, Seoul, Korea
| | - Soo Han Yoon
- Department of Neurosurgery, Ajou University School of Medicine, Suwon, Korea
| | - Sun Yong Kim
- Department of Radiology, Ajou University School of Medicine, Suwon, Korea
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220
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Boyle M, Hurley A, Curtis E. Skull asymmetry as an unusual presentation of an intracranial tumour. Pediatr Neurosurg 2012; 48:333-4. [PMID: 23816888 DOI: 10.1159/000351548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Accepted: 04/18/2013] [Indexed: 11/19/2022]
Affiliation(s)
- Michael Boyle
- Department of General and Developmental Pediatrics, The Adelaide and Meath Hospital Incorporating the National Children's Hospital, Tallaght, Ireland.
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221
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Gonzalez PN, Oyhenart EE, Hallgrímsson B. Effects of environmental perturbations during postnatal development on the phenotypic integration of the skull. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART B, MOLECULAR AND DEVELOPMENTAL EVOLUTION 2011; 316:547-61. [PMID: 21826787 PMCID: PMC4050671 DOI: 10.1002/jez.b.21430] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Revised: 06/14/2011] [Accepted: 06/16/2011] [Indexed: 12/22/2022]
Abstract
Integration and modularity are fundamental determinants of how natural selection effects evolutionary change in complex multivariate traits. Interest in the study of the specific developmental basis of integration through experimental approaches is fairly recent and it has mainly focused on its genetic determinants. In this study, we present evidence that postnatal environmental perturbations can modify the covariance structure by influencing the variance of some developmental processes relative to the variances of other processes that contribute to such structure. We analyzed the effects of the reduction of nutrient supply in different ontogenetic stages (i.e. before and after weaning, and from birth to adulthood) in Rattus norvegicus. Our results show that this environmental perturbation alters the phenotypic variation/covariation structure of the principal modules of the skull (base, vault, and face). The covariance matrices of different treatment groups exhibit low correlations and are significantly different, indicating that the treatments influence covariance structure. Postnatal nutrient restriction also increases the variance of somatic growth. This increased variance drives an increase in overall integration of cranial morphology through the correlated allometric effects of size variation. The extent of this increase in integration depends on the time and duration of the nutritional restriction. These results support the conclusion that environmental perturbations can influence integration and thus covariance structure via developmental plasticity.
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222
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Laue K, Pogoda HM, Daniel PB, van Haeringen A, Alanay Y, von Ameln S, Rachwalski M, Morgan T, Gray MJ, Breuning MH, Sawyer GM, Sutherland-Smith AJ, Nikkels PG, Kubisch C, Bloch W, Wollnik B, Hammerschmidt M, Robertson SP. Craniosynostosis and multiple skeletal anomalies in humans and zebrafish result from a defect in the localized degradation of retinoic acid. Am J Hum Genet 2011; 89:595-606. [PMID: 22019272 DOI: 10.1016/j.ajhg.2011.09.015] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2011] [Revised: 09/20/2011] [Accepted: 09/23/2011] [Indexed: 01/23/2023] Open
Abstract
Excess exogenous retinoic acid (RA) has been well documented to have teratogenic effects in the limb and craniofacial skeleton. Malformations that have been observed in this context include craniosynostosis, a common developmental defect of the skull that occurs in 1 in 2500 individuals and results from premature fusion of the cranial sutures. Despite these observations, a physiological role for RA during suture formation has not been demonstrated. Here, we present evidence that genetically based alterations in RA signaling interfere with human development. We have identified human null and hypomorphic mutations in the gene encoding the RA-degrading enzyme CYP26B1 that lead to skeletal and craniofacial anomalies, including fusions of long bones, calvarial bone hypoplasia, and craniosynostosis. Analyses of murine embryos exposed to a chemical inhibitor of Cyp26 enzymes and zebrafish lines with mutations in cyp26b1 suggest that the endochondral bone fusions are due to unrestricted chondrogenesis at the presumptive sites of joint formation within cartilaginous templates, whereas craniosynostosis is induced by a defect in osteoblastic differentiation. Ultrastructural analysis, in situ expression studies, and in vitro quantitative RT-PCR experiments of cellular markers of osseous differentiation indicate that the most likely cause for these phenomena is aberrant osteoblast-osteocyte transitioning. This work reveals a physiological role for RA in partitioning skeletal elements and in the maintenance of cranial suture patency.
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Affiliation(s)
- Kathrin Laue
- Institute of Developmental Biology, University of Cologne, D-50674 Cologne, Germany
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223
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Molecular analysis of coronal perisutural tissues in a craniosynostotic rabbit model using polymerase chain reaction suppression subtractive hybridization. Plast Reconstr Surg 2011; 128:95-103. [PMID: 21701325 DOI: 10.1097/prs.0b013e31821740e8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND In the United States, the incidence of craniosynostosis (premature fusion of the sutures of the cranial vault) is one in 2000 to 3000 live births. The condition can cause increased intracranial pressure, severely altered head shape, and mental retardation. The authors have previously described a colony of rabbits with heritable coronal suture synostosis. This model has been instrumental in describing the postsurgical craniofacial growth associated with craniosynostosis. The molecular analysis of this model has been limited by the lack of molecular tools for use in rabbits. To understand the pathogenesis of craniosynostosis, the authors compared gene expression in perisutural tissues between wild-type and craniosynostotic rabbits using polymerase chain reaction suppression subtractive hybridization. METHODS Suppression subtractive hybridization polymerase chain reaction was performed on RNA derived from pooled samples of calvariae from 10-day-old wild-type (n = 3) and craniosynostotic (n = 3) rabbits to obtain cDNA clones enriched in either wild-type tissues (underexpressed in craniosynostotic tissue) or craniosynostotic tissues (overexpressed in craniosynostotic compared with wild-type). RESULTS Differential expression was identified for approximately 140 recovered cDNA clones up-regulated in craniosynostotic tissues and 130 recovered clones for wild-type tissues. Of these, four genes were confirmed by quantitative reverse-transcriptase polymerase chain reaction as being overexpressed in craniosynostotic sutural tissue: β-globin (HBB), osteopontin (SPP1), osteonectin (SPARC), and cathepsin K (CTSK). Two genes were confirmed to be underexpressed in the craniosynostotic samples: collagen 3, alpha 1 (COL3A1) and ring finger protein 12 (RNF12). CONCLUSION The differential expression of these gene products in our naturally occurring craniosynostotic model appears to be the result of differences in the normal bone formation/resorption pathway.
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224
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Bruner E, De La Cuétara JM, Holloway R. A Bivariate Approach to the Variation of the Parietal Curvature in the Genus Homo. Anat Rec (Hoboken) 2011; 294:1548-56. [DOI: 10.1002/ar.21450] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Accepted: 06/10/2011] [Indexed: 11/08/2022]
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225
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Keppler-Noreuil KM, Blumhorst C, Sapp JC, Brinckman D, Johnston J, Nopoulos PC, Biesecker LG. Brain tissue- and region-specific abnormalities on volumetric MRI scans in 21 patients with Bardet-Biedl syndrome (BBS). BMC MEDICAL GENETICS 2011; 12:101. [PMID: 21794117 PMCID: PMC3199749 DOI: 10.1186/1471-2350-12-101] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/11/2011] [Accepted: 07/27/2011] [Indexed: 11/10/2022]
Abstract
Background Bardet-Biedl syndrome (BBS) is a heterogeneous human disorder inherited in an autosomal recessive pattern, and characterized by the primary findings of obesity, polydactyly, hypogonadism, and learning and behavioural problems. BBS mouse models have a neuroanatomical phenotype consisting of third and lateral ventriculomegaly, thinning of the cerebral cortex, and reduction in the size of the corpus striatum and hippocampus. These abnormalities raise the question of whether humans with BBS have a characteristic morphologic brain phenotype. Further, although behavioral, developmental, neurological and motor defects have been noted in patients with BBS, to date, there are limited reports of brain findings in BBS. The present study represents the largest systematic evaluation for the presence of structural brain malformations and/or progressive changes, which may contribute to these functional problems. Methods A case-control study of 21 patients, most aged 13-35 years, except for 2 patients aged 4 and 8 years, who were diagnosed with BBS by clinical criteria and genetic analysis of known BBS genes, and were evaluated by qualitative and volumetric brain MRI scans. Healthy controls were matched 3:1 by age, sex and race. Statistical analysis was performed using SAS language with SAS STAT procedures. Results All 21 patients with BBS were found to have statistically significant region- and tissue-specific patterns of brain abnormalities. There was 1) normal intracranial volume; 2) reduced white matter in all regions of the brain, but most in the occipital region; 3) preserved gray matter volume, with increased cerebral cortex volume in only the occipital lobe; 4) reduced gray matter in the subcortical regions of the brain, including the caudate, putamen and thalamus, but not in the cerebellum; and 5) increased cerebrospinal fluid volume. Conclusions There are distinct and characteristic abnormalities in tissue- and region- specific volumes of the brain in patients with BBS, which parallel the findings, described in BBS mutant mouse models. Some of these brain abnormalities may be progressive and associated with the reported neurological and behavioral problems. Further future correlation of these MRI scan findings with detailed neurologic and neuropsychological exams together with genotype data will provide better understanding of the pathophysiology of BBS.
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Affiliation(s)
- Kim M Keppler-Noreuil
- Department of Pediatrics, Division of Medical Genetics, The University of Iowa Children's Hospital, Iowa City, IA 52242, USA.
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226
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Behr B, Longaker MT, Quarto N. Craniosynostosis of coronal suture in twist1 mice occurs through endochondral ossification recapitulating the physiological closure of posterior frontal suture. Front Physiol 2011; 2:37. [PMID: 21811467 PMCID: PMC3143731 DOI: 10.3389/fphys.2011.00037] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Accepted: 06/28/2011] [Indexed: 12/03/2022] Open
Abstract
Craniosynostosis, the premature closure of cranial suture, is a pathologic condition that affects 1/2000 live births. Saethre-Chotzen syndrome is a genetic condition characterized by craniosynostosis. The Saethre-Chotzen syndrome, which is defined by loss-of-function mutations in the TWIST gene, is the second most prevalent craniosynostosis. Although much of the genetics and phenotypes in craniosynostosis syndromes is understood, less is known about the underlying ossification mechanism during suture closure. We have previously demonstrated that physiological closure of the posterior frontal suture occurs through endochondral ossification. Moreover, we revealed that antagonizing canonical Wnt-signaling in the sagittal suture leads to endochondral ossification of the suture mesenchyme and sagittal synostosis, presumably by inhibiting Twist1. Classic Saethre-Chotzen syndrome is characterized by coronal synostosis, and the haploinsufficient Twist1+/− mice represents a suitable model for studying this syndrome. Thus, we seeked to understand the underlying ossification process in coronal craniosynostosis in Twist1+/− mice. Our data indicate that coronal suture closure in Twist1+/− mice occurs between postnatal day 9 and 13 by endochondral ossification, as shown by histology, gene expression analysis, and immunohistochemistry. In conclusion, this study reveals that coronal craniosynostosis in Twist1+/− mice occurs through endochondral ossification. Moreover, it suggests that haploinsufficiency of Twist1 gene, a target of canonical Wnt-signaling, and inhibitor of chondrogenesis, mimics conditions of inactive canonical Wnt-signaling leading to craniosynostosis.
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Affiliation(s)
- Björn Behr
- Hagey Laboratory for Regenerative Medicine, Department of Surgery, Division of Plastic and Reconstructive Surgery, Stanford University School of Medicine Stanford, CA, USA
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227
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Nieminen P, Morgan NV, Fenwick AL, Parmanen S, Veistinen L, Mikkola ML, van der Spek PJ, Giraud A, Judd L, Arte S, Brueton LA, Wall SA, Mathijssen IMJ, Maher ER, Wilkie AOM, Kreiborg S, Thesleff I. Inactivation of IL11 signaling causes craniosynostosis, delayed tooth eruption, and supernumerary teeth. Am J Hum Genet 2011; 89:67-81. [PMID: 21741611 DOI: 10.1016/j.ajhg.2011.05.024] [Citation(s) in RCA: 136] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 05/13/2011] [Accepted: 05/25/2011] [Indexed: 01/30/2023] Open
Abstract
Craniosynostosis and supernumerary teeth most often occur as isolated developmental anomalies, but they are also separately manifested in several malformation syndromes. Here, we describe a human syndrome featuring craniosynostosis, maxillary hypoplasia, delayed tooth eruption, and supernumerary teeth. We performed homozygosity mapping in three unrelated consanguineous Pakistani families and localized the syndrome to a region in chromosome 9. Mutational analysis of candidate genes in the region revealed that all affected children harbored homozygous missense mutations (c.662C>G [p.Pro221Arg], c.734C>G [p.Ser245Cys], or c.886C>T [p.Arg296Trp]) in IL11RA (encoding interleukin 11 receptor, alpha) on chromosome 9p13.3. In addition, a homozygous nonsense mutation, c.475C>T (p.Gln159X), and a homozygous duplication, c.916_924dup (p.Thr306_Ser308dup), were observed in two north European families. In cell-transfection experiments, the p.Arg296Trp mutation rendered the receptor unable to mediate the IL11 signal, indicating that the mutation causes loss of IL11RA function. We also observed disturbed cranial growth and suture activity in the Il11ra null mutant mice, in which reduced size and remodeling of limb bones has been previously described. We conclude that IL11 signaling is essential for the normal development of craniofacial bones and teeth and that its function is to restrict suture fusion and tooth number. The results open up the possibility of modulation of IL11 signaling for the treatment of craniosynostosis.
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Affiliation(s)
- Pekka Nieminen
- Institute of Dentistry, Biomedicum, University of Helsinki, Finland.
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228
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Abstract
BACKGROUND Suture reformation after strip craniectomy for nonsyndromic sagittal synostosis remains an inconsistent and underreported phenomenon. Although several theories have been proposed to account for the fate of the cranial defect, no explanation accurately matches clinical experience with the appearance of reformed sutures, ectopic sutures, and complete defect ossification postoperatively. METHODS AND RESULTS We review the case of a 7-year-old boy who formed a parasagittal suture at the defect margin after strip craniectomy for nonsyndromic sagittal synostosis. We review the literature and the clinical experiences of previous authors. CONCLUSIONS The pathogenesis of suture reformation and the biomechanical forces shaping suture formation are still poorly understood. Previous reports of postoperative suture reformation offer inconclusive evidence as to whether a pathologic suture, an abnormal cranial base, or a combination of biomechanical forces plays the larger role. It remains an open question as to whether a single underlying mechanism can explain suture reformation or if there are instead multiple causes.
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229
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Richardson S, Browne ML, Rasmussen SA, Druschel CM, Sun L, Jabs EW, Romitti PA. Associations between periconceptional alcohol consumption and craniosynostosis, omphalocele, and gastroschisis. ACTA ACUST UNITED AC 2011; 91:623-30. [PMID: 21630421 DOI: 10.1002/bdra.20823] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 02/16/2011] [Accepted: 03/12/2011] [Indexed: 11/10/2022]
Abstract
BACKGROUND Alcohol consumption during pregnancy is known to be associated with certain birth defects, but the risk of other birth defects is less certain. The authors examined associations between maternal alcohol consumption during pregnancy and craniosynostosis, omphalocele, and gastroschisis among participants in the National Birth Defects Prevention Study, a large, multicenter case-control study. METHODS A total of 6622 control infants and 1768 infants with birth defects delivered from 1997-2005 were included in the present analysis. Maternal alcohol consumption was assessed as any periconceptional consumption (1 month prepregnancy through the third pregnancy month), and by quantity-frequency, duration, and beverage type. Alcohol consumption throughout pregnancy was explored for craniosynostosis since the period of development may extend beyond the first trimester. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regression analysis. OR were adjusted for age, race/ethnicity, and state of residence at time of infant's birth. Gastroschisis OR were also adjusted for periconceptional smoking. RESULTS Periconceptional alcohol consumption and craniosynostosis showed little evidence of an association (OR = 0.92; CI: 0.78-1.08), but alcohol consumption in the second (OR = 0.65; CI: 0.47-0.92) and third trimesters (OR = 0.68; CI: 0.49-0.95) was inversely associated with craniosynostosis. Periconceptional alcohol consumption was associated with omphalocele (OR = 1.50; CI: 1.15-1.96) and gastroschisis (OR = 1.40; CI: 1.17-1.67). CONCLUSIONS Results suggest that maternal periconceptional alcohol consumption is associated with omphalocele and gastroschisis, and second and third trimester alcohol consumption are inversely associated with craniosynostosis.
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Affiliation(s)
- Sandra Richardson
- Congenital Malformations Registry, Bureau of Environmental and Occupational Epidemiology, New York State Department of Health, Troy, USA.
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230
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Zollikofer CPE, Weissmann JD. A bidirectional interface growth model for cranial interosseous suture morphogenesis. J Anat 2011; 219:100-14. [PMID: 21539540 DOI: 10.1111/j.1469-7580.2011.01386.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Interosseous sutures exhibit highly variable patterns of interdigitation and corrugation. Recent research has identified fundamental molecular mechanisms of suture formation, and computer models have been used to simulate suture morphogenesis. However, the role of bone strain in the development of complex sutures is largely unknown, and measuring suture morphologies beyond the evaluation of fractal dimensions remains a challenge. Here we propose a morphogenetic model of suture formation, which is based on the paradigm of Laplacian interface growth. Computer simulations of suture morphogenesis under various boundary conditions generate a wide variety of synthetic sutural forms. Their morphologies are quantified with a combination of Fourier analysis and principal components analysis, and compared with natural morphological variation in an ontogenetic sample of human interparietal suture lines. Morphometric analyses indicate that natural sutural shapes exhibit a complex distribution in morphospace. The distribution of synthetic sutures closely matches the natural distribution. In both natural and synthetic systems, sutural complexity increases during morphogenesis. Exploration of the parameter space of the simulation system indicates that variation in strain and/or morphogen sensitivity and viscosity of sutural tissue may be key factors in generating the large variability of natural suture complexity.
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231
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Blocking bone morphogenetic protein function using in vivo noggin therapy does not rescue premature suture fusion in rabbits with delayed-onset craniosynostosis. Plast Reconstr Surg 2011; 127:1163-1172. [PMID: 21364419 DOI: 10.1097/prs.0b013e318205f23b] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Craniosynostosis is defined as the premature fusion of one or more cranial sutures. Bone morphogenetic proteins (BMPs), regulators of ossification, have been implicated in premature suture fusion. Noggin, an extracellular BMP inhibitor, has been shown experimentally to inhibit resynostosis following surgery. The present study was designed to test the hypothesis that BMP inhibition using noggin therapy may rescue sutures destined to fuse by inhibiting initial ossification. METHODS Twenty-six, 10-day old rabbits with familial, delayed-onset, coronal suture synostosis were randomly divided into three groups: (1) the sham surgical control group, (2) the bovine serum albumin-treated group [10 μg/suture (protein/vehicle controls)], and (3) the noggin therapy group (10 μg/suture; experimental group). Sutural growth was monitored by radiopaque markers implanted at 10 days of age. At 25 days, the bovine serum albumin or noggin was combined with a slow-resorbing collagen vehicle and injected subperiosteally above the coronal suture. Somatic and sutural growth data were collected at 10, 25, 42, and 84 days of age. Coronal sutures were harvested at 84 days to histologically assess fusion. RESULTS Results showed no significant (p > 0.05) differences in suture separation at any age. Suture fusion assessed by histomorphology did not differ among the three groups. Although previous data showed noggin to inhibit postoperative resynostosis in this craniosynostotic rabbit model, here there was no effect on initial suture fusion. CONCLUSION These results suggest that in this rabbit model of craniosynostosis, BMPs do not play a role in the pathogenesis of craniosynostosis and only play a role in postoperative bony wound healing.
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Sandell LL, Iulianella A, Melton KR, Lynn M, Walker M, Inman KE, Bhatt S, Leroux-Berger M, Crawford M, Jones NC, Dennis JF, Trainor PA. A phenotype-driven ENU mutagenesis screen identifies novel alleles with functional roles in early mouse craniofacial development. Genesis 2011; 49:342-59. [PMID: 21305688 DOI: 10.1002/dvg.20727] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Accepted: 01/24/2011] [Indexed: 01/13/2023]
Abstract
Proper craniofacial development begins during gastrulation and requires the coordinated integration of each germ layer tissue (ectoderm, mesoderm, and endoderm) and its derivatives in concert with the precise regulation of cell proliferation, migration, and differentiation. Neural crest cells, which are derived from ectoderm, are a migratory progenitor cell population that generates most of the cartilage, bone, and connective tissue of the head and face. Neural crest cell development is regulated by a combination of intrinsic cell autonomous signals acquired during their formation, balanced with extrinsic signals from tissues with which the neural crest cells interact during their migration and differentiation. Although craniofacial anomalies are typically attributed to defects in neural crest cell development, the cause may be intrinsic or extrinsic. Therefore, we performed a phenotype-driven ENU mutagenesis screen in mice with the aim of identifying novel alleles in an unbiased manner, that are critically required for early craniofacial development. Here we describe 10 new mutant lines, which exhibit phenotypes affecting frontonasal and pharyngeal arch patterning, neural and vascular development as well as sensory organ morphogenesis. Interestingly, our data imply that neural crest cells and endothelial cells may employ similar developmental programs and be interdependent during early embryogenesis, which collectively is critical for normal craniofacial morphogenesis. Furthermore our novel mutants that model human conditions such as exencephaly, craniorachischisis, DiGeorge, and Velocardiofacial sydnromes could be very useful in furthering our understanding of the complexities of specific human diseases.
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Affiliation(s)
- Lisa L Sandell
- Stowers Institute for Medical Research, Kansas City, Missouri, USA
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233
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Curnoe D. A 150-year conundrum: cranial robusticity and its bearing on the origin of aboriginal australians. INTERNATIONAL JOURNAL OF EVOLUTIONARY BIOLOGY 2011; 2011:632484. [PMID: 21350636 PMCID: PMC3039414 DOI: 10.4061/2011/632484] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Accepted: 12/16/2010] [Indexed: 01/08/2023]
Abstract
The origin of Aboriginal Australians has been a central question of palaeoanthropology since its inception during the 19th Century. Moreover, the idea that Australians could trace their ancestry to a non-modern Pleistocene population such as Homo erectus in Southeast Asia have existed for more than 100 years, being explicitly linked to cranial robusticity. It is argued here that in order to resolve this issue a new program of research should be embraced, one aiming to test the full range of alternative explanations for robust morphology. Recent developments in the morphological sciences, especially relating to the ontogeny of the cranium indicate that character atomisation, an approach underpinning phylogenetic reconstruction, is fraught with difficulties. This leads to the conclusion that phylogenetic-based explanations for robusticity should be reconsidered and a more parsimonious approach to explaining Aboriginal Australian origins taken. One that takes proper account of the complex processes involved in the growth of the human cranium rather than just assuming natural selection to explain every subtle variation seen in past populations. In doing so, the null hypothesis that robusticity might result from phenotypic plasticity alone cannot be rejected, a position at odds with both reticulate and deep-time continuity models of Australian origins.
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Affiliation(s)
- Darren Curnoe
- School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, NSW 2052, Australia
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234
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Abstract
Craniosynostosis, defined as the premature fusion of the cranial sutures, presents many challenges in classification and treatment. At least 20% of cases are caused by specific single gene mutations or chromosome abnormalities. This article maps out approaches to clinical assessment of a child presenting with an unusual head shape, and illustrates how genetic analysis can contribute to diagnosis and management.
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Affiliation(s)
- David Johnson
- Oxford Craniofacial Unit, Oxford Radcliffe Hospitals NHS Trust, John Radcliffe Hospital, Oxford, UK
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235
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Klopocki E, Lohan S, Brancati F, Koll R, Brehm A, Seemann P, Dathe K, Stricker S, Hecht J, Bosse K, Betz RC, Garaci FG, Dallapiccola B, Jain M, Muenke M, Ng VC, Chan W, Chan D, Mundlos S. Copy-number variations involving the IHH locus are associated with syndactyly and craniosynostosis. Am J Hum Genet 2011; 88:70-5. [PMID: 21167467 DOI: 10.1016/j.ajhg.2010.11.006] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 11/10/2010] [Accepted: 11/12/2010] [Indexed: 11/26/2022] Open
Abstract
Indian hedgehog (IHH) is a secreted signaling molecule of the hedgehog family known to play important roles in the regulation of chondrocyte differentiation, cortical bone formation, and the development of joints. Here, we describe that copy-number variations of the IHH locus involving conserved noncoding elements (CNEs) are associated with syndactyly and craniosynostosis. These CNEs are able to drive reporter gene expression in a pattern highly similar to wild-type Ihh expression. We postulate that the observed duplications lead to a misexpression and/or overexpression of IHH and by this affect the complex regulatory signaling network during digit and skull development.
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236
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Parsons KJ, Andreeva V, James Cooper W, Yelick PC, Craig Albertson R. Morphogenesis of the zebrafish jaw: development beyond the embryo. Methods Cell Biol 2011; 101:225-48. [PMID: 21550447 DOI: 10.1016/b978-0-12-387036-0.00011-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The zebrafish has emerged as an important model for vertebrate development as it relates to human health and disease. Work in this system has provided significant insights into the variety of genetic signals that direct the cellular activities and tissue interactions necessary for proper assembly of the pharyngeal skeleton. Unfortunately our understanding of craniofacial development beyond embryonic stages is far less complete. Stated another way, we know a great deal about the early patterning of the skull, but we know comparatively little about how mature craniofacial shape is determined and maintained over time. Here we propose ways to expand the current molecular genetic paradigm beyond the embryo to gain an understanding of the processes and mechanisms that guide growth and remodeling of mineralized craniofacial, skeletal, and dental tissues. First, we discuss sources of adult mutant phenotypes that can be used to study of postembryonic development. Next, we review salient quantitative methods that are necessary to define complex adult phenotypes. We also discuss how other organismal systems can be used to inform and complement studies in zebrafish. We conclude by discussing the implications for such studies within the context of furthering an understanding of the etiology and pathophysiology of human craniofacial malformations, as well as informing an understanding of adaptive craniofacial variation among natural populations.
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Affiliation(s)
- Kevin J Parsons
- Department of Biology, Syracuse University, Syracuse, NY, USA
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237
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Stricker S, Mundlos S. FGF and ROR2 receptor tyrosine kinase signaling in human skeletal development. Curr Top Dev Biol 2011; 97:179-206. [PMID: 22074606 DOI: 10.1016/b978-0-12-385975-4.00013-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Skeletal malformations are among the most frequent developmental disturbances in humans. In the past years, progress has been made in unraveling the molecular mechanisms that govern skeletal development by the use of animal models as well as by the identification of numerous mutations that cause human skeletal syndromes. Receptor tyrosine kinases have critical roles in embryonic development. During formation of the skeletal system, the fibroblast growth factor receptor (FGFR) family plays major roles in the formation of cranial, axial, and appendicular bones. Another player of relevance to skeletal development is the unusual receptor tyrosine kinase ROR2, the function of which is as interesting as it is complex. In this chapter, we review the involvement of FGFR signaling in human skeletal disease and provide an update on the growing knowledge of ROR2.
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Affiliation(s)
- Sigmar Stricker
- Development and Disease Group, Max Planck-Institute for Molecular Genetics, Berlin, Germany
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238
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Nopoulos PC, Aylward EH, Ross CA, Mills JA, Langbehn DR, Johnson HJ, Magnotta VA, Pierson RK, Beglinger LJ, Nance MA, Barker RA, Paulsen JS. Smaller intracranial volume in prodromal Huntington's disease: evidence for abnormal neurodevelopment. Brain 2011; 134:137-42. [PMID: 20923788 PMCID: PMC3025719 DOI: 10.1093/brain/awq280] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Revised: 07/12/2010] [Accepted: 08/12/2010] [Indexed: 12/14/2022] Open
Abstract
Huntington's disease is an autosomal dominant brain disease. Although conceptualized as a neurodegenerative disease of the striatum, a growing number of studies challenge this classic concept of Huntington's disease aetiology. Intracranial volume is the tissue and fluid within the calvarium and is a representation of the maximal brain growth obtained during development. The current study reports intracranial volume obtained from an magnetic resonance imaging brain scan in a sample of subjects (n = 707) who have undergone presymptomatic gene testing. Participants who are gene-expanded but not yet manifesting the disease (prodromal Huntington's disease) are compared with subjects who are non-gene expanded. The prodromal males had significantly smaller intracranial volume measures with a mean volume that was 4% lower compared with controls. Although the prodromal females had smaller intracranial volume measures compared with their controls, this was not significant. The current findings suggest that mutant huntingtin can cause abnormal development, which may contribute to the pathogenesis of Huntington's disease.
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Affiliation(s)
- Peggy C. Nopoulos
- 1 Department of Psychiatry, The University of Iowa Roy and Lucille Carver College of Medicine, Iowa, IA 52242, USA
- 2 Department of Pediatrics, The University of Iowa Roy and Lucille Carver College of Medicine, Iowa City, IA 52242, USA
- 3 Department of Neurology, The University of Iowa Roy and Lucille Carver College of Medicine, Iowa City, IA 52242, USA
| | | | - Christopher A. Ross
- 5 Division of Neurology, Pharmacology and Neuroscience, Johns Hopkins University, Baltimore, MD, USA
| | - James A. Mills
- 1 Department of Psychiatry, The University of Iowa Roy and Lucille Carver College of Medicine, Iowa, IA 52242, USA
| | - Douglas R. Langbehn
- 1 Department of Psychiatry, The University of Iowa Roy and Lucille Carver College of Medicine, Iowa, IA 52242, USA
| | - Hans J. Johnson
- 1 Department of Psychiatry, The University of Iowa Roy and Lucille Carver College of Medicine, Iowa, IA 52242, USA
| | - Vincent A. Magnotta
- 1 Department of Psychiatry, The University of Iowa Roy and Lucille Carver College of Medicine, Iowa, IA 52242, USA
- 6 Department of Radiology, The University of Iowa Roy and Lucille Carver College of Medicine, Iowa City, IA 52242, USA
| | - Ronald K. Pierson
- 1 Department of Psychiatry, The University of Iowa Roy and Lucille Carver College of Medicine, Iowa, IA 52242, USA
| | - Leigh J. Beglinger
- 1 Department of Psychiatry, The University of Iowa Roy and Lucille Carver College of Medicine, Iowa, IA 52242, USA
| | - Martha A. Nance
- 7 Hennepin County Medical Center, Department of Neurosciences, Saint Louis Park, MN, USA
| | - Roger A. Barker
- 8 Cambridge Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, CB2 0PY, UK
| | - Jane S. Paulsen
- 1 Department of Psychiatry, The University of Iowa Roy and Lucille Carver College of Medicine, Iowa, IA 52242, USA
- 3 Department of Neurology, The University of Iowa Roy and Lucille Carver College of Medicine, Iowa City, IA 52242, USA
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239
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Carmichael SL, Rasmussen SA, Lammer EJ, Ma C, Shaw GM. Craniosynostosis and nutrient intake during pregnancy. ACTA ACUST UNITED AC 2010; 88:1032-9. [PMID: 20842649 DOI: 10.1002/bdra.20717] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 06/02/2010] [Accepted: 07/02/2010] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To examine the association of craniosynostosis with maternal intake of folic acid-containing supplements and dietary nutrients. METHODS The study included deliveries from 1997 to 2005 from the National Birth Defects Prevention Study. Nonsyndromic infants with craniosynostosis (n = 815) were compared to nonmalformed, population-based liveborn control infants (n = 6789), by estimating adjusted odds ratios (AORs) and 95% confidence intervals (CIs) from logistic regression models that included mother's age, parity, race-ethnicity, education, body mass index, smoking, alcohol, fertility treatments, plurality, and study center. We compared quartiles of intake and specified nutrients as continuous. RESULTS Intake of folic acid-containing supplements was not associated with craniosynostosis (AORs were close to 1). Analyses of dietary nutrients were restricted to mothers who took supplements during the first trimester (i.e., most women). Based on continuous specifications of nutrients, sagittal synostosis risk was significantly lower among women with higher intake of riboflavin and vitamins B₆, E, and C; metopic synostosis risk was significantly higher among women with higher intakes of choline and vitamin B₁₂; and coronal synostosis risk was significantly lower among women with higher intake of methionine and vitamin C. As examples, AORs for sagittal synostosis among women with intakes of vitamin B₆ and riboflavin in the highest versus lowest quartiles were 0.4 (95% CI, 0.2-0.6) and 0.5 (95% CI, 0.3-0.7), respectively. CONCLUSION This analysis suggests that dietary intake of certain nutrients may be associated with craniosynostosis, and results may vary by suture type.
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Affiliation(s)
- Suzan L Carmichael
- California Research Division, March of Dimes Foundation, Oakland, California, USA.
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240
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Trainor PA. Craniofacial birth defects: The role of neural crest cells in the etiology and pathogenesis of Treacher Collins syndrome and the potential for prevention. Am J Med Genet A 2010; 152A:2984-94. [PMID: 20734335 DOI: 10.1002/ajmg.a.33454] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Accepted: 02/14/2010] [Indexed: 11/10/2022]
Abstract
Of all the babies born with birth defects, approximately one-third display anomalies of the head and face [Gorlin et al., 1990] including cleft lip, cleft palate, small or absent facial and skull bones and improperly formed nose, eyes, ears, and teeth. Craniofacial disorders are a primary cause of infant mortality and have serious lifetime functional, esthetic, and social consequences that are devastating to both children and parents alike. Comprehensive surgery, dental care, psychological counseling, and rehabilitation can help ameliorate-specific problems but at great cost over many years which dramatically affects national health care budgets. For example, the Center for Disease Control and Prevention estimates that the lifetime cost of treating the children born each year with cleft lip and/or cleft palate alone to be US$697 million. Treating craniofacial malformations, of which in excess of 700 distinct syndromes have been described, through comprehensive, well-coordinated and integrated strategies can provide satisfactory management of individual conditions, however, the results are often variable and rarely fully corrective. Therefore, better techniques for tissue repair and regeneration need to be developed and therapeutic avenues of prevention need to be explored in order to eliminate the devastating consequences of head and facial birth defects. To do this requires a thorough understanding of the normal events that control craniofacial development during embryogenesis. This review therefore focuses on recent advances in our understanding of the basic etiology and pathogenesis of a rare craniofacial disorder known as Treacher Collins syndrome and emerging prospects for prevention that may have broad application to congenital craniofacial birth defects.
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Affiliation(s)
- Paul A Trainor
- Stowers Institute for Medical Research, Kansas City, Missouri 64110, USA.
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241
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Yen HY, Ting MC, Maxson RE. Jagged1 functions downstream of Twist1 in the specification of the coronal suture and the formation of a boundary between osteogenic and non-osteogenic cells. Dev Biol 2010; 347:258-70. [PMID: 20727876 DOI: 10.1016/j.ydbio.2010.08.010] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 08/03/2010] [Accepted: 08/06/2010] [Indexed: 01/10/2023]
Abstract
The Notch pathway is crucial for a wide variety of developmental processes including the formation of tissue boundaries. That it may function in calvarial suture development and figure in the pathophysiology of craniosynostosis was suggested by the demonstration that heterozygous loss of function of JAGGED1 in humans can cause Alagille syndrome, which has craniosynostosis as a feature. We used conditional gene targeting to examine the role of Jagged1 in the development of the skull vault. We demonstrate that Jagged1 is expressed in a layer of mesoderm-derived sutural cells that lie along the osteogenic-non-osteogenic boundary. We show that inactivation of Jagged1 in the mesodermal compartment of the coronal suture, but not in the neural crest compartment, results in craniosynostosis. Mesodermal inactivation of Jagged1 also results in changes in the identity of sutural cells prior to overt osteogenic differentiation, as well as defects in the boundary between osteogenic and non-osteogenic compartments at the coronal suture. These changes, surprisingly, are associated with increased expression of Notch2 and the Notch effector, Hes1, in the sutural mesenchyme. They are also associated with an increase in nuclear β-catenin. In Twist1 mutants, Jagged1 expression in the suture is reduced substantially, suggesting an epistatic relationship between Twist1 and Jagged1. Consistent with such a relationship, Twist1-Jagged1 double heterozygotes exhibit a substantial increase in the severity of craniosynostosis over individual heterozygotes. Our results thus suggest that Jagged1 is an effector of Twist1 in coronal suture development.
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Affiliation(s)
- Hai-Yun Yen
- Department of Biochemistry and Molecular Biology, Norris Cancer Hospital, University of Southern California Keck School of Medicine, 1441 Eastlake Avenue, Los Angeles, CA 90089-9176, USA
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242
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Wilkie AO, Byren JC, Hurst JA, Jayamohan J, Johnson D, Knight SJL, Lester T, Richards PG, Twigg SRF, Wall SA. Prevalence and complications of single-gene and chromosomal disorders in craniosynostosis. Pediatrics 2010; 126:e391-400. [PMID: 20643727 PMCID: PMC3535761 DOI: 10.1542/peds.2009-3491] [Citation(s) in RCA: 184] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVES We describe the first cohort-based analysis of the impact of genetic disorders in craniosynostosis. We aimed to refine the understanding of prognoses and pathogenesis and to provide rational criteria for clinical genetic testing. METHODS We undertook targeted molecular genetic and cytogenetic testing for 326 children who required surgery because of craniosynostosis, were born in 1993-2002, presented to a single craniofacial unit, and were monitored until the end of 2007. RESULTS Eighty-four children (and 64 relatives) had pathologic genetic alterations (86% single-gene mutations and 14% chromosomal abnormalities). The FGFR3 P250R mutation was the single largest contributor (24%) to the genetic group. Genetic diagnoses accounted for 21% of all craniosynostosis cases and were associated with increased rates of many complications. Children with an initial clinical diagnosis of nonsyndromic craniosynostosis were more likely to have a causative mutation if the synostoses were unicoronal or bicoronal (10 of 48 cases) than if they were sagittal or metopic (0 of 55 cases; P = .0003). Repeat craniofacial surgery was required for 58% of children with single-gene mutations but only 17% of those with chromosomal abnormalities (P = .01). CONCLUSIONS Clinical genetic assessment is critical for the treatment of children with craniosynostosis. Genetic testing of nonsyndromic cases (at least for FGFR3 P250R and FGFR2 exons IIIa/c) should be targeted to patients with coronal or multisuture synostoses. Single-gene disorders that disrupt physiologic signaling in the cranial sutures often require reoperation, whereas chromosomal abnormalities follow a more-indolent course, which suggests a different, secondary origin of the associated craniosynostosis.
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Affiliation(s)
- Andrew O.M. Wilkie
- Weatherall Institute of Molecular Medicine, University of Oxford
,Oxford Craniofacial Unit, Oxford Radcliffe Hospitals NHS Trust, John Radcliffe Hospital
,Department of Clinical Genetics, Oxford Radcliffe Hospitals NHS Trust, Churchill Hospital
| | - Jo C. Byren
- Oxford Craniofacial Unit, Oxford Radcliffe Hospitals NHS Trust, John Radcliffe Hospital
| | - Jane A. Hurst
- Department of Clinical Genetics, Oxford Radcliffe Hospitals NHS Trust, Churchill Hospital
| | - Jayaratnam Jayamohan
- Oxford Craniofacial Unit, Oxford Radcliffe Hospitals NHS Trust, John Radcliffe Hospital
| | - David Johnson
- Oxford Craniofacial Unit, Oxford Radcliffe Hospitals NHS Trust, John Radcliffe Hospital
| | - Samantha J. L. Knight
- NIHR Biomedical Research Centre and Wellcome Trust Centre for Human Genetics, University of Oxford
| | - Tracy Lester
- Genetics Laboratories, Oxford Radcliffe Hospitals NHS Trust, Churchill Hospital, Oxford, United Kingdom
| | - Peter G. Richards
- Oxford Craniofacial Unit, Oxford Radcliffe Hospitals NHS Trust, John Radcliffe Hospital
| | | | - Steven A. Wall
- Oxford Craniofacial Unit, Oxford Radcliffe Hospitals NHS Trust, John Radcliffe Hospital
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243
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Zhang X, Zara J, Siu RK, Ting K, Soo C. The role of NELL-1, a growth factor associated with craniosynostosis, in promoting bone regeneration. J Dent Res 2010; 89:865-78. [PMID: 20647499 DOI: 10.1177/0022034510376401] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Efforts to enhance bone regeneration in orthopedic and dental cases have grown steadily for the past decade, in line with increasingly sophisticated regenerative medicine. To meet the unprecedented demand for novel osteospecific growth factors with fewer adverse effects compared with those of existing adjuncts such as BMPs, our group has identified a craniosynostosis-associated secreted molecule, NELL-1, which is a potent growth factor that is highly specific to the osteochondral lineage, and has demonstrated robust induction of bone in multiple in vivo models from rodents to pre-clinical large animals. NELL-1 is preferentially expressed in osteoblasts under direct transcriptional control of Runx2, and is well-regulated during skeletal development. NELL-1/Nell-1 can promote orthotopic bone regeneration via either intramembranous or endochondral ossification, both within and outside of the craniofacial complex. Unlike BMP-2, Nell-1 cannot initiate ectopic bone formation in muscle, but can induce bone marrow stromal cells (BMSCs) to form bone in a mouse muscle pouch model, exhibiting specificity that BMPs lack. In addition, synergistic osteogenic effects of Nell-1 and BMP combotherapy have been observed, and are likely due to distinct differences in their signaling pathways. NELL-1's unique role as a novel osteoinductive growth factor makes it an attractive alternative with promise for future clinical applications. [Note: NELL-1 and NELL-1 indicate the human gene and protein, respectively; Nell-1 and Nell-1 indicate the mouse gene and protein, respectively.]
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Affiliation(s)
- X Zhang
- Dental and Craniofacial Research Institute, University of California, Los Angeles, 10833 Le Conte Avenue, CHS 73-060, Los Angeles, CA 90095, USA.
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244
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Heuzé Y, Boyadjiev SA, Marsh JL, Kane AA, Cherkez E, Boggan JE, Richtsmeier JT. New insights into the relationship between suture closure and craniofacial dysmorphology in sagittal nonsyndromic craniosynostosis. J Anat 2010; 217:85-96. [PMID: 20572900 DOI: 10.1111/j.1469-7580.2010.01258.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Premature closure of the sagittal suture occurs as an isolated (nonsyndromic) birth defect or as a syndromic anomaly in combination with other congenital dysmorphologies. The genetic causes of sagittal nonsyndromic craniosynostosis (NSC) remain unknown. Although variation of the dysmorphic (scaphocephaly) skull shape of sagittal NSC cases has been acknowledged, this variation has not been quantitatively studied three-dimensionally (3D). We have analyzed the computed tomography skull images of 43 infants (aged 0.9-9 months) with sagittal NSC using anatomical landmarks and semilandmarks to quantify and characterize the within-sample phenotypic variation. Suture closure patterns were defined by dividing the sagittal suture into three sections (anterior, central, posterior) and coding each section as 'closed' or 'fused'. Principal components analysis of the Procrustes shape coordinates representing the skull shape of 43 cases of NSC did not separate individuals by sex, chronological age, or dental stages of the deciduous maxillary first molar. However, analysis of suture closure pattern allowed separation of these data. The central section of the sagittal suture appears to be the first to fuse. Then, at least two different developmental paths towards complete fusion of the sagittal suture exist; either the anterior section or the posterior section is the second to fuse. Results indicate that according to the sequence of sagittal suture closure patterns, different craniofacial complex shapes are observed. The relationship between craniofacial shape and suture closure indicates not only which suture fused prematurely (in our case the sagittal suture), but also the pattern of the suture closure. Whether these patterns indicate differences in etiology cannot be determined with our data and requires analysis of longitudinal data, most appropriately of animal models where prenatal conditions can be monitored.
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Affiliation(s)
- Yann Heuzé
- Department of Anthropology, The Pennsylvania State University, University Park, PA 16802, USA.
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245
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Behr B, Longaker MT, Quarto N. Differential activation of canonical Wnt signaling determines cranial sutures fate: a novel mechanism for sagittal suture craniosynostosis. Dev Biol 2010; 344:922-40. [PMID: 20547147 DOI: 10.1016/j.ydbio.2010.06.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Revised: 05/21/2010] [Accepted: 06/04/2010] [Indexed: 10/19/2022]
Abstract
Premature closure of cranial sutures, which serve as growth centers for the skull vault, result in craniosynostosis. In the mouse posterior frontal (PF) suture closes by endochondral ossification, whereas sagittal (SAG) remain patent life time, although both are neural crest tissue derived. We therefore, investigated why cranial sutures of same tissue origin adopt a different fate. We demonstrated that closure of the PF suture is tightly regulated by canonical Wnt signaling, whereas patency of the SAG suture is achieved by constantly activated canonical Wnt signaling. Importantly, the fate of PF and SAG sutures can be reversed by manipulating Wnt signaling. Continuous activation of canonical Wnt signaling in the PF suture inhibits endochondral ossification and therefore, suture closure, In contrast, inhibition of canonical Wnt signaling in the SAG suture, upon treatment with Wnt antagonists results in endochondral ossification and suture closure. Thus, inhibition of canonical Wnt signaling in the SAG suture phenocopies craniosynostosis. Moreover, mice haploinsufficient for Twist1, a target gene of canonical Wnt signaling which inhibits chondrogenesis, have sagittal craniosynostosis. We propose that regulation of canonical Wnt signaling is of crucial importance during the physiological patterning of PF and SAG sutures. Importantly, dysregulation of this pathway may lead to craniosynostosis.
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Affiliation(s)
- Björn Behr
- Children's Surgical Research Program, Department of Surgery, Division of Plastic and Reconstructive Surgery, Stanford University School of Medicine, Stanford, CA, USA
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246
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Bruner E. Morphological Differences in the Parietal Lobes within the Human Genus. CURRENT ANTHROPOLOGY 2010. [DOI: 10.1086/650729] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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247
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Ermakov S, Rosenbaum MG, Malkin I, Livshits G. Family-based study of association between ENPP1 genetic variants and craniofacial morphology. Ann Hum Biol 2010; 37:754-66. [PMID: 20446819 DOI: 10.3109/03014461003639231] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND Human craniofacial morphology is characterized by considerable diversity among individuals. The ENPP1 gene is essential for bone physiology. However, the potential effects of its genetic variants on head size phenotypes have not yet been studied. AIM The aim of this research was to investigate the association of polymorphisms in the ENPP1 locus with normal variability of craniofacial phenotypes. SUBJECTS AND METHODS Fourteen SNPs and 13 haplotypes in the ENPP1 locus were tested for association with six head size traits in 1042 Western Eurasian individuals. RESULTS The most significant and consistent association was observed between upper facial height and the polymorphisms located near the promoter region and upstream from ENPP1 gene (p = 0.00009), which remained significant after adjustment for multiple testing. Additionally, association signals were detected between head breadths and lower face height, and markers residing in or close to the promoter and 3' untranslated regions of the ENPP1 gene (p < 0.05). CONCLUSIONS The findings obtained in this study suggest that the upstream, promoter and 3' untranslated regions in the ENPP1 locus harbor genetic variants affecting different aspects of craniofacial morphology. Further research is required to validate the relevancy of the potentially functional ENPP1 regions to normal and pathologic craniofacial growth.
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Affiliation(s)
- Sergey Ermakov
- Human Population Biology Research Unit, Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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Effects of Flutamide Therapy on Craniofacial Growth and Development in a Model of Craniosynostosis. J Craniofac Surg 2010; 21:711-8. [DOI: 10.1097/scs.0b013e3181d80a36] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Roybal PG, Wu NL, Sun J, Ting MC, Schafer CA, Maxson RE. Inactivation of Msx1 and Msx2 in neural crest reveals an unexpected role in suppressing heterotopic bone formation in the head. Dev Biol 2010; 343:28-39. [PMID: 20398647 DOI: 10.1016/j.ydbio.2010.04.007] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Revised: 04/06/2010] [Accepted: 04/07/2010] [Indexed: 10/19/2022]
Abstract
In an effort to understand the morphogenetic forces that shape the bones of the skull, we inactivated Msx1 and Msx2 conditionally in neural crest. We show that Wnt1-Cre inactivation of up to three Msx1/2 alleles results in a progressively larger defect in the neural crest-derived frontal bone. Unexpectedly, in embryos lacking all four Msx1/2 alleles, the large defect is filled in with mispatterned bone consisting of ectopic islands of bone between the reduced frontal bones, just anterior to the parietal bones. The bone is derived from neural crest, not mesoderm, and, from DiI cell marking experiments, originates in a normally non-osteogenic layer of cells through which the rudiment elongates apically. Associated with the heterotopic osteogenesis is an upregulation of Bmp signaling in this cell layer. Prevention of this upregulation by implantation of noggin-soaked beads in head explants also prevented heterotopic bone formation. These results suggest that Msx genes have a dual role in calvarial development: They are required for the differentiation and proliferation of osteogenic cells within rudiments, and they are also required to suppress an osteogenic program in a cell layer within which the rudiments grow. We suggest that the inactivation of this repressive activity may be one cause of Wormian bones, ectopic bones that are a feature of a variety of pathological conditions in which calvarial bone development is compromised.
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Affiliation(s)
- Paul G Roybal
- Department of Biochemistry and Molecular Biology, Norris Cancer Hospital, University of Southern California Keck School of Medicine, 1441 Eastlake Avenue, Los Angeles, CA 90089-9176, USA
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Wang Y, Sun M, Uhlhorn VL, Zhou X, Peter I, Martinez-Abadias N, Hill CA, Percival CJ, Richtsmeier JT, Huso DL, Jabs EW. Activation of p38 MAPK pathway in the skull abnormalities of Apert syndrome Fgfr2(+P253R) mice. BMC DEVELOPMENTAL BIOLOGY 2010; 10:22. [PMID: 20175913 PMCID: PMC2838826 DOI: 10.1186/1471-213x-10-22] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2009] [Accepted: 02/22/2010] [Indexed: 12/02/2022]
Abstract
Background Apert syndrome is characterized by craniosynostosis and limb abnormalities and is primarily caused by FGFR2 +/P253R and +/S252W mutations. The former mutation is present in approximately one third whereas the latter mutation is present in two-thirds of the patients with this condition. We previously reported an inbred transgenic mouse model with the Fgfr2 +/S252W mutation on the C57BL/6J background for Apert syndrome. Here we present a mouse model for the Fgfr2+/P253R mutation. Results We generated inbred Fgfr2+/P253R mice on the same C56BL/6J genetic background and analyzed their skeletal abnormalities. 3D micro-CT scans of the skulls of the Fgfr2+/P253R mice revealed that the skull length was shortened with the length of the anterior cranial base significantly shorter than that of the Fgfr2+/S252W mice at P0. The Fgfr2+/P253R mice presented with synostosis of the coronal suture and proximate fronts with disorganized cellularity in sagittal and lambdoid sutures. Abnormal osteogenesis and proliferation were observed at the developing coronal suture and long bones of the Fgfr2+/P253R mice as in the Fgfr2+/S252W mice. Activation of mitogen-activated protein kinases (MAPK) was observed in the Fgfr2+/P253R neurocranium with an increase in phosphorylated p38 as well as ERK1/2, whereas phosphorylated AKT and PKCα were not obviously changed as compared to those of wild-type controls. There were localized phenotypic and molecular variations among individual embryos with different mutations and among those with the same mutation. Conclusions Our in vivo studies demonstrated that the Fgfr2 +/P253R mutation resulted in mice with cranial features that resemble those of the Fgfr2+/S252W mice and human Apert syndrome. Activated p38 in addition to the ERK1/2 signaling pathways may mediate the mutant neurocranial phenotype. Though Apert syndrome is traditionally thought to be a consistent phenotype, our results suggest localized and regional variations in the phenotypes that characterize Apert syndrome.
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Affiliation(s)
- Yingli Wang
- Department of Genetics and Genomic Sciences, Mount Sinai School of Medicine, New York, New York, USA.
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