Search results for "Dysostosis"

Autosomal recessive variations of TBX6 , from congenital scoliosis to spondylocostal dysostosis

2017

International audience; Proximal 16p11.2 microdeletions are recurrent microdeletions with an overall prevalence of 0.03%. In patients with segmentation defects of the vertebra (SDV), a burden of this microdeletion was observed with TBX6 as a candidate gene for SDV. In a published cohort of patients with congenital scoliosis (CS), TBX6 haploinsufficiency was compound heterozygous with a common haplotype. Besides, a single three-generation family with spondylocostal dysostosis (SCD) was reported with a heterozygous stop-loss of TBX6. These observations questioned both on the inheritance mode and on the variable expressivity associated with TBX6-associated SDV. Based on a national recruitment …

Orbital volume and shape in Treacher Collins syndrome

2018

Orbito-palpebral reconstruction is a challenge in Treacher Collins syndrome (TCS). This study investigates orbital phenotypes in TCS using cephalometry and orbital shape analysis. Eighteen TCS and 52 control patients were included in this study, using the Dr Warehouse database. Orbital cephalometry was based on 20 landmarks, 10 planes, 16 angles, and 22 distances. Orbits were segmented. Registration-based, age-specific mean models were generated using semi-automatic segmentation, and aligned and compared using color-coded distance maps - mean absolute distance (MAD), Hausdorff distance (HD), and Dice similarity coefficient (DSC). Symmetry was assessed by mirroring and DSC computing. Central…

Phenotype determining alleles in GM1 gangliosidosis patients bearing novel GLB1 mutations.

2010

Hofer D, Paul K, Fantur K, Beck M, Roubergue A, Vellodi A, Poorthuis BJ, Michelakakis H, Plecko B, Paschke E. Phenotype determining alleles in GM1 gangliosidosis patients bearing novel GLB1 mutations. GM1 gangliosidosis manifests with progressive psychomotor deterioration and dysostosis of infantile, juvenile, or adult onset, caused by alterations in the structural gene coding for lysosomal acid s-galactosidase (GLB1). In addition, allelic variants of this gene can result in Morquio B disease (MBD), a phenotype with dysostosis multiplex and entire lack of neurologic involvement. More than 100 sequence alterations in the GLB1 gene have been identified so far, but only few could be proven to …

Molecular Genetics of Frontonasal Dysplasia

2018

Mutations in LMX1B cause abnormal skeletal patterning and renal dysplasia in nail patella syndrome

1998

The LIM-homeodomain protein Lmxlb plays a central role in dorso-ventral patterning of the vertebrate limb1. Targeted disruption of Lmxlb results in skeletal defects including hypoplas-tic nails, absent patellae and a unique form of renal dysplasia (see accompanying manuscript by H. Chen et al.; ref. 2). These features are reminiscent of the dominantly inherited skeletal malformation nail patella syndrome (NFS). We show that LMX1B maps to the NFS locus and that three independent NFS patients carry de novo heterozygous mutations in this gene. Functional studies show that one of these mutations disrupts sequence-specific DNA binding, while the other two mutations result in premature terminatio…

Diagnostic strategy in segmentation defect of the vertebrae: a retrospective study of 73 patients

2018

BackgroundSegmentation defects of the vertebrae (SDV) are non-specific features found in various syndromes. The molecular bases of SDV are not fully elucidated due to the wide range of phenotypes and classification issues. The genes involved are in the Notch signalling pathway, which is a key system in somitogenesis. Here we report on mutations identified in a diagnosis cohort of SDV. We focused on spondylocostal dysostosis (SCD) and the phenotype of these patients in order to establish a diagnostic strategy when confronted with SDV.Patients and methodsWe used DNA samples from a cohort of 73 patients and performed targeted sequencing of the five known SCD-causing genes (DLL3,MESP2,LFNG,HES7…

Spondylo-costal dysostosis in two siblings

1992

Two new cases of Spondylo-Costal Dysostosis (SCD) are reported in two siblings with strikingly similar skeletal abnormalities. Parental consanguinity documents in this family an autosomal recessive inheritance of trait. Clinical variability of SCD is discussed on the basis of clinical and radiological features. Its genetic heterogeneity is pointed out even considering the occurrence of cases with autosomal dominant as well as recessive inheritance.

Cholesteatoma of the hypotympanum in a patient with Treacher Collins syndrome

2014

In the present article we report a cholesteatoma of the hypotympanum extending to the jugular foramen in a 16-year-old male with Treacher Collins syndrome. Preoperative imaging excluded jugular paraganglioma and set the diagnosis of cholesteatoma. We discuss the operative treatment via a large hypotympanotomy and creation of an open hypotympanic cavity. To the authors' knowledge this is the first description of hypotympanal cholesteatoma with such an extension, being treated through this approach.

Boy with pseudohypoparathyroidism type 1a caused byGNASgene mutation (deltaN377), Crouzon-like craniosynostosis, and severe trauma-induced bleeding

2009

We report on a 6-month-old boy with craniosynostosis, pseudohypoparathyroidism type 1a (PHP1A), and a GNAS gene mutation. He had synostoses of the coronal, frontal, and sagittal sutures, brachyturricephaly, and hydrocephaly. He also had congenital hypothyroidism, round face, full cheeks, shortness of limbs, mild developmental delay, and muscular hypotonia. Because of progressive hydrocephaly, the synostosis was corrected surgically but circulatory decompensation led to disseminated intravascular coagulation and cerebral infarctions. Our patient died 8 days later. Postmortem molecular studies of GNAS, the gene for guanine nucleotide-binding protein, alpha-stimulating activity polypeptide (ge…

Q289P mutation in the FGFR2 gene: first report in a patient with type 1 Pfeiffer syndrome.

2008

When normal development and growth of the calvarial sutures is disrupted, craniosynostosis (premature calvarial suture fusion) may result. Classical craniosynostosis syndromes are autosomal dominant traits and include Apert, Pfeiffer, Crouzon, Jackson-Weiss, and Saethre-Chotzen syndromes. In these conditions, there is premature fusion of skull bones leading to an abnormal head shape, ocular hypertelorism with proptosis, and midface hypoplasia. It is known that mutations in the fibroblast growth factor receptors 1, 2, and 3 cause craniosynostosis. We report on a child with a clinically diagnosed Pfeiffer syndrome that shows the missense point mutation Q289P in exon 8 of the FGFR2 gene. This …