Ultrastructural study of a hitherto unknown disturbance of the synthesis of collagen precursor molecules in human cutis.

The ultrastructural characteristics of on hitherto unknown disturbance of collagen precursor molecules in human skin were studied. A severe disturbance of the synthesis of collagen exists at the procollagen stage. The paracrystalline accumulation of a form of procollagen in the tubes of the smooth ER and an increase in its appearance in the extracellular space, distinguish this clinical picture from all other previously described connective tissue disorders, especially from Dermatosparaxis and Ehlers-Danlos syndrome type VII. For this clinical picture we suggest the name "Dermatosparaxis endoplasmatica".