Osteogenesis Imperfecta: Biochemical Aspects and Molecular Defects

Abstract

Osteogenesis imperfecta (OI) is a general disorder of connective tissue which primarily affects the biomechanical stability of the bones. It is inherited in either a recessive or dominant mode and spontaneous mutations have also been found. It is a rare disease with a frequence of 1:20 000 newborns which implies that some 2000–3000 affected persons live in the FRG. Clinical, genetic and radiological criteria have been used to divide this disease into four subgroups (1). Inspite of major shortcomings this classification has been accepted by a majority of clinicians and scientists all over the world hoping that it could facilitate the data exchange and promote a better understanding of molecular mechanisms causing this disease. In the recent years the effects on improving the basic understanding of 01 focused on the search for abnormalities in the gene structure and metabolism of collagen. Two major reasons stimulated this research field: (1) collagen is the predominant structural component of bones and other connective tissue forms; (2) the progress made in basic research fields concerning this polymorphous protein was of such dimensions that a detailed experimental comparison of a healthy with an affected status would make the successful identification of a molecular defect rather likely.