Article

WNT5A mutations in patients with autosomal dominant Robinow syndrome

Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minnesota, USA.
Developmental Dynamics (Impact Factor: 2.67). 11/2009; 239(1):327-37. DOI: 10.1002/dvdy.22156
Source: PubMed

ABSTRACT Robinow syndrome is a skeletal dysplasia with both autosomal dominant and autosomal recessive inheritance patterns. It is characterized by short stature, limb shortening, genital hypoplasia, and craniofacial abnormalities. The etiology of dominant Robinow syndrome is unknown; however, the phenotypically more severe autosomal recessive form of Robinow syndrome has been associated with mutations in the orphan tyrosine kinase receptor, ROR2, which has recently been identified as a putative WNT5A receptor. Here, we show that two different missense mutations in WNT5A, which result in amino acid substitutions of highly conserved cysteines, are associated with autosomal dominant Robinow syndrome. One mutation has been found in all living affected members of the original family described by Meinhard Robinow and another in a second unrelated patient. These missense mutations result in decreased WNT5A activity in functional assays of zebrafish and Xenopus development. This work suggests that a WNT5A/ROR2 signal transduction pathway is important in human craniofacial and skeletal development and that proper formation and growth of these structures is sensitive to variations in WNT5A function.

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Available from: Stephen Carl Ekker, Aug 31, 2015
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    • "AD RS is similar but less severe than the autosomal recessive (ROR2-related) form, especially regarding the skeletal defects (4). Missense mutations in WNT5A that result in amino acid substitutions of highly conserved cysteines have been reported in AD RS (17). ROR2 has recently been identified as a putative WNT5A receptor. "
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    ABSTRACT: Ob­jec­ti­ve: Robinow syndrome (RS) is an extremely rare genetic disorder characterized by short-limbed dwarfism, defects in vertebral segmentation and abnormalities in the head, face and external genitalia. Mutations in the ROR2 gene cause autosomal recessive RS (RRS) whereas mutations in WNT5A are responsible for the autosomal dominant (AD) form of RS. In AD Robinow patients, oral manifestations are more prominent, while hemivertebrae and scoliosis rarely occur and facial abnormalities tend to be milder. Methods: Three unrelated patients from different parts of India were studied. These patients were diagnosed as RRS due to presence of characteristic fetal facies, mesomelia, short stature, micropenis, hemivertebrae and rib abnormalities. One of the patients had fetal facies and micropenis but unusually mild skeletal features. This patient’s mother had mild affection in the form of short stature and prominent eyes. Testosterone response to human chorionic gonadotropin was investigated in two patients and were normal. The exons and exon-intron boundaries of the ROR2 gene were sequenced for all probands. Bioinformatics analysis was done for putative variants using SIFT, PolyPhen2 and Mutation Taster. Results: Patients 1, 2 and 3 were homozygous for c.G545A or p.C182Y in exon 5, c.227G>A or p.G76D in exon 3 and c.668G>A or p.C223Y in exon 6 respectively. Prenatal diagnosis could be performed in an ongoing pregnancy in one family and the fetus was confirmed to be unaffected. Conclusion: ROR2 mutations were documented for the first time in the Indian population. Knowledge of the molecular basis of the disorder served to provide accurate counseling and prenatal diagnosis to the families.
    Journal of Clinical Research in Pediatric Endocrinology 06/2014; 6(2):79-83. DOI:10.4274/Jcrpe.1233
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    • "As Wnt5a genetically interacts with Vangl2 and Wnt5a has been found to bind Ror2, a receptor tyrosine kinase [16,65], we further hypothesized that Wnt5a transduces its signal through a novel receptor complex containing Vangl2 and Ror2. Mutations in both WNT5A and ROR2 are found to cause Robinow syndrome characterized by shortened limb dwarfism [8-11]. To test this hypothesis further, we generated Ror2 and Vangl2 double mutant embryos and found that they phenocopied the Wnt5a-/- embryo in the limb, craniofacial processes and the tail. "
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    ABSTRACT: Cell signaling mediated by morphogens is essential to coordinate growth and patterning, two key processes that govern the formation of a complex multi-cellular organism. During growth and patterning, cells are specified by both quantitative and directional information. While quantitative information regulates cell proliferation and differentiation, directional information is conveyed in the form of cell polarities instructed by local and global cues. Major morphogens like Wnts play critical roles in embryonic development and they are also important in maintaining tissue homeostasis. Abnormal regulation of these signaling events leads to a diverse array of devastating diseases including cancer. Wnts transduce their signals through several distinct pathways and they regulate vertebrate embryonic development by providing both quantitative and directional information. Here, taking the developing skeletal system as an example, we review our work on Wnt signaling pathways in various aspects of development. We focus particularly on our most recent findings that showed that in vertebrates, Wnt5a acts as a global cue to establishing planar cell polarity (PCP). Our work suggests that Wnt morphogens regulate development by integrating quantitative and directional information. Our work also provides important insights in disease like Robinow syndrome, brachydactyly type B1 (BDB1) and spina bifida, which can be caused by human mutations in the Wnt/PCP signaling pathway.
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    • "Among the differentially expressed genes specifically up-regulated in hereditary HGPS was the Wnt5a ligand, a member of the non-canonical Wnt signaling pathway, whose pathogenic role in vivo could be evidenced by increased expression in skin from an affected LMNAK542/K542N carrier. Wnt5a signaling is essential for normal developmental morphogenesis resulting in abnormal craniofacial and skeletal development in Wnt5a null mice [49], [50], and Robinow Syndrome in humans [51]. Moreover, Wnt5a was shown to be an important player in the decision-making process whether bone marrow mesenchymal cells differentiate into adipocytes or osteoblasts [45]. "
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    PLoS ONE 06/2011; 6(6):e21433. DOI:10.1371/journal.pone.0021433 · 3.23 Impact Factor
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