• Ror2;
  • Robinow syndrome;
  • somitogenesis;
  • development of limb;
  • craniofacies;
  • genital


Robinow syndrome (RS) is a human dwarfism syndrome characterized by mesomelic limb shortening, vertebral and craniofacial malformations and small external genitals. We have analyzed Ror2-/- mice as a model for the developmental pathology of RS. Our results demonstrate that vertebral malformations in Ror2-/- mice are due to reductions in the presomitic mesoderm and defects in somitogenesis. Mesomelic limb shortening in Ror2-/- mice is a consequence of perturbed chondrocyte differentiation. Moreover, we show that the craniofacial phenotype is caused by a midline outgrowth defect. Ror2 expression in the genital tubercle and its reduced size in Ror2-/- mice makes it likely that Ror2 is involved in genital development. In conclusion, our findings suggest that Ror2 is essential at multiple sites during development. The Ror2-/- mouse provides a suitable model that may help to explain many of the underlying developmental malformations in individuals with Robinow syndrome. Developmental Dynamics 229:400–410, 2004, © 2004 Wiley-Liss, Inc.