@article{StangeDesirKakaretal.2015, author = {Stange, Katja and D{\´e}sir, Julie and Kakar, Naseebullah and Mueller, Thomas D. and Budde, Birgit S. and Gordon, Christopher T. and Horn, Denise and Seemann, Petra and Borck, Guntram}, title = {A hypomorphic BMPR1B mutation causes du Pan acromesomelic dysplasia}, series = {Orphanet Journal of Rare Diseases}, volume = {10}, journal = {Orphanet Journal of Rare Diseases}, number = {84}, doi = {10.1186/s13023-015-0299-5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-151650}, year = {2015}, abstract = {Background: Grebe dysplasia, Hunter-Thompson dysplasia, and du Pan dysplasia constitute a spectrum of skeletal dysplasias inherited as an autosomal recessive trait characterized by short stature, severe acromesomelic shortening of the limbs, and normal axial skeleton. The majority of patients with these disorders have biallelic loss-of-function mutations of GDF5. In single instances, Grebe dysplasia and a Grebe dysplasia-like phenotype with genital anomalies have been shown to be caused by mutations in BMPR1B, encoding a GDF5 receptor. Methods: We clinically and radiologically characterised an acromesomelic chondrodysplasia in an adult woman born to consanguineous parents. We sequenced GDF5 and BMPR1B on DNA of the proposita. We performed 3D structural analysis and luciferase reporter assays to functionally investigate the identified BMPR1B mutation. Results: We extend the genotype-phenotype correlation in the acromesomelic chondrodysplasias by showing that the milder du Pan dysplasia can be caused by a hypomorphic BMPR1B mutation. We show that the homozygous c.91C>T, p.(Arg31Cys) mutation causing du Pan dysplasia leads to a significant loss of BMPR1B function, but to a lesser extent than the previously reported p.Cys53Arg mutation that results in the more severe Grebe dysplasia. Conclusions: The phenotypic severity gradient of the clinically and radiologically related acromesomelic chondrodysplasia spectrum of skeletal disorders may be due to the extent of functional impairment of the ligand-receptor pair GDF5-BMPR1B.}, language = {en} } @article{DubailHuberChantepieetal.2018, author = {Dubail, Johanne and Huber, C{\´e}line and Chantepie, Sandrine and Sonntag, Stephan and T{\"u}ys{\"u}z, Beyhan and Mihci, Ercan and Gordon, Christopher T. and Steichen-Gersdorf, Elisabeth and Amiel, Jeanne and Nur, Banu and Stolte-Dijkstra, Irene and van Eerde, Albertien M. and van Gassen, Koen L. and Breugem, Corstiaan C. and Stegmann, Alexander and Lekszas, Caroline and Maroofian, Reza and Karimiani, Ehsan Ghayoor and Bruneel, Arnaud and Seta, Nathalie and Munnich, Arnold and Papy-Garcia, Dulce and De La Dure-Molla, Muriel and Cormier-Daire, Val{\´e}rie}, title = {SLC10A7 mutations cause a skeletal dysplasia with amelogenesis imperfecta mediated by GAG biosynthesis defects}, series = {Nature Communications}, volume = {9}, journal = {Nature Communications}, doi = {10.1038/s41467-018-05191-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226377}, year = {2018}, abstract = {Skeletal dysplasia with multiple dislocations are severe disorders characterized by dislocations of large joints and short stature. The majority of them have been linked to pathogenic variants in genes encoding glycosyltransferases, sulfotransferases or epimerases required for glycosaminoglycan synthesis. Using exome sequencing, we identify homozygous mutations in SLC10A7 in six individuals with skeletal dysplasia with multiple dislocations and amelogenesis imperfecta. SLC10A7 encodes a 10-transmembrane-domain transporter located at the plasma membrane. Functional studies in vitro demonstrate that SLC10A7 mutations reduce SLC10A7 protein expression. We generate a Slc10a7-/- mouse model, which displays shortened long bones, growth plate disorganization and tooth enamel anomalies, recapitulating the human phenotype. Furthermore, we identify decreased heparan sulfate levels in Slc10a7-/- mouse cartilage and patient fibroblasts. Finally, we find an abnormal N-glycoprotein electrophoretic profile in patient blood samples. Together, our findings support the involvement of SLC10A7 in glycosaminoglycan synthesis and specifically in skeletal development.}, language = {en} }