Specific collagen mRNAs elucidate the histogenetic relationship between the growth plate, the tissue in the ossification groove of Ranvier, and the cambium layer of the adjacent periosteum. A preliminary report

In situ hybridization was employed to study cellular phenotypes in the ossification groove of Ranvier in young rabbits. The expression of Type II collagen mRNA was seen in chondrocytes in all layers of the growth plate. Messenger RNA for the cartilage-specific Type II collagen was also detected in cells of the inner layer in the ossification groove and of the cambium layer of the adjacent periosteum, providing strong evidence for the views of Ranvier that these cells originate in the growth plate. These findings modify the interpretation of the pathogenesis of diseases of the growing skeleton.