Fig. 6. Schematic representation of paralogous Hox axial skeleton phenotypes. Somite-derived, primaxial skeletal elements that exhibit anterior homeotic transformations in paralogous mutants are in red. Lateral plate-derived structures affected in paralogous mutants are in blue. Note that Hox5, Hox6 and Hox9 mutant phenotypes are offset in their AP extent for defects in the somite-derived (red) and lateral plate-derived (blue) skeleton. The yellow shading highlights somite-derived AP regions that are affected in adjacent paralogous mutant groups. In each case, the overlapping regions of phenotype display distinct vertebral morphologies for each paralogous mutant. The green asterisks in the Hox9 mutant reflect the posterior shift of the axial skeleton. Mice normally possess 28-30 caudal vertebrae. Only 15 are represented here for simplicity. Despite changes in the number of caudal vertebrae in Hox9 and Hox11 paralogous mutants, the same average total numbers of vertebrae are present in all of the paralogous mutants depicted in this diagram, and are the same as in control animals.