@article {538, title = {Expanding the genetic architecture and phenotypic spectrum in the skeletal ciliopathies.}, journal = {Hum Mutat}, volume = {39}, year = {2018}, month = {2018 01}, pages = {152-166}, abstract = {

Defects in the biosynthesis and/or function of primary cilia cause a spectrum of disorders collectively referred to as ciliopathies. A subset of these disorders is distinguished by profound abnormalities of the skeleton that include a long narrow chest with markedly short ribs, extremely short limbs, and polydactyly. These include the perinatal lethal short-rib polydactyly syndromes (SRPS) and the less severe asphyxiating thoracic dystrophy (ATD), Ellis-van Creveld (EVC) syndrome, and cranioectodermal dysplasia (CED) phenotypes. To identify new genes and define the spectrum of mutations in the skeletal ciliopathies, we analyzed 152 unrelated families with SRPS, ATD, and EVC. Causal variants were discovered in 14 genes in 120 families, including one newly associated gene and two genes previously associated with other ciliopathies. These three genes encode components of three different ciliary complexes; FUZ, which encodes a planar cell polarity complex molecule; TRAF3IP1, which encodes an anterograde ciliary transport protein; and LBR, which encodes a nuclear membrane protein with sterol reductase activity. The results established the molecular basis of SRPS type IV, in which mutations were identified in four different ciliary genes. The data provide systematic insight regarding the genotypes associated with a large cohort of these genetically heterogeneous phenotypes and identified new ciliary components required for normal skeletal development.

}, keywords = {Ciliopathies, Cytoplasmic Dyneins, Genetic Association Studies, Genetic Markers, Genetic Variation, Genotype, Humans, Mutation, Phenotype, Proteins, Radiography, Skeleton, Whole Exome Sequencing}, issn = {1098-1004}, doi = {10.1002/humu.23362}, author = {Zhang, Wenjuan and Taylor, S Paige and Ennis, Hayley A and Forlenza, Kimberly N and Duran, Ivan and Li, Bing and Sanchez, Jorge A Ortiz and Nevarez, Lisette and Nickerson, Deborah A and Bamshad, Michael and Lachman, Ralph S and Krakow, Deborah and Cohn, Daniel H} } @article {349, title = {A postnatal role for embryonic myosin revealed by MYH3 mutations that alter TGFβ signaling and cause autosomal dominant spondylocarpotarsal synostosis.}, journal = {Sci Rep}, volume = {7}, year = {2017}, month = {2017 02 16}, pages = {41803}, abstract = {

Spondylocarpotarsal synostosis (SCT) is a skeletal disorder characterized by progressive vertebral, carpal and tarsal fusions, and mild short stature. The majority of affected individuals have an autosomal recessive form of SCT and are homozygous or compound heterozygous for nonsense mutations in the gene that encodes the cytoskeletal protein filamin B (FLNB), but a subset do not have FLNB mutations. Exome sequence analysis of three SCT patients negative for FLNB mutations identified an autosomal dominant form of the disease due to heterozygosity for missense or nonsense mutations in MYH3, which encodes embryonic myosin. Cells transfected with the MYH3 missense mutations had reduced TGFβ signaling, revealing a regulatory role for embryonic myosin in the TGFβ signaling pathway. In wild-type mice, there was persistent postnatal expression of embryonic myosin in the small muscles joining the neural arches of the spine suggesting that loss of myosin function in these muscles contribute to the disease. Our findings demonstrate that dominant mutations in MYH3 underlie autosomal dominant SCT, identify a postnatal role for embryonic myosin and suggest that altered regulation of signal transduction in the muscles within the spine may lead to the development of vertebral fusions.

}, keywords = {Abnormalities, Multiple, Alleles, Bone Morphogenetic Proteins, Cytoskeletal Proteins, Female, Genes, Dominant, Genotype, Humans, Lumbar Vertebrae, Male, Musculoskeletal Diseases, Mutation, Myosins, Phenotype, Radiography, Scoliosis, Signal Transduction, Synostosis, Thoracic Vertebrae, Transforming Growth Factor beta, Whole Exome Sequencing}, issn = {2045-2322}, doi = {10.1038/srep41803}, author = {Zieba, Jennifer and Zhang, Wenjuan and Chong, Jessica X and Forlenza, Kimberly N and Martin, Jorge H and Heard, Kelly and Grange, Dorothy K and Butler, Merlin G and Kleefstra, Tjitske and Lachman, Ralph S and Nickerson, Deborah and Regnier, Michael and Cohn, Daniel H and Bamshad, Michael and Krakow, Deborah} } @article {35, title = {IFT52 mutations destabilize anterograde complex assembly, disrupt ciliogenesis and result in short rib polydactyly syndrome.}, journal = {Hum Mol Genet}, volume = {25}, year = {2016}, month = {2016 Sep 15}, pages = {4012-4020}, abstract = {

The short-rib polydactyly syndromes (SRPS) encompass a radiographically and genetically heterogeneous group of skeletal ciliopathies that are characterized by a long narrow chest, short extremities, and variable occurrence of polydactyly. Radiographic abnormalities include undermineralization of the calvarium, shortened and bowed appendicular bones, trident shaped acetabula and polydactyly. In a case of SRPS we identified compound heterozygosity for mutations in IFT52, which encodes a component of the anterograde intraflagellar transport complex. The IFT52 mutant cells synthesized a significantly reduced amount of IFT52 protein, leading to reduced synthesis of IFT74, IFT81, IFT88 and ARL13B, other key anterograde complex members. Ciliogenesis was also disrupted in the mutant cells, with a 60\% reduction in the presence of cilia on mutant cells and loss of cilia length regulation for the cells with cilia. These data demonstrate that IFT52 is essential for anterograde complex integrity and for the biosynthesis and maintenance of cilia. The data identify a new locus for SRPS and show that IFT52 mutations result in a ciliopathy with primary effects on the skeleton.

}, keywords = {Carrier Proteins, Cilia, Ciliopathies, Cytoskeletal Proteins, Flagella, Humans, Intracellular Signaling Peptides and Proteins, Multiprotein Complexes, Muscle Proteins, Mutation, Short Rib-Polydactyly Syndrome, Skeleton, Tumor Suppressor Proteins}, issn = {1460-2083}, doi = {10.1093/hmg/ddw241}, author = {Zhang, Wenjuan and Taylor, S Paige and Nevarez, Lisette and Lachman, Ralph S and Nickerson, Deborah A and Bamshad, Michael and Krakow, Deborah and Cohn, Daniel H} }