Spatiotemporal disorder in the axial skeleton development of the Mesp2-null mouse: A model of spondylocostal dysostosis and spondylothoracic dysostosis

► We examine developing spine in Mesp2-null mice. ► Our analyses demonstrate the developing vertebral bodies in Mesp2-null mice to be extensively fused with rare insertions of intervertebral discs. ► The differentiation of vertebral chondrocytes in Mesp2-null mice is spatially disordered and largely delayed. ► Spatiotemporal alterations in endochondral ossification play a significant role in the pathogenesis of SCDO and STDO.