Molecular defects in the chondrodysplasias

There has been a recent explosion of knowledge concerning the biochemical and molecular defects in the skeletal dysplasias. Through both the candidate gene approach and positional cloning, specific gene defects that produce the skeletal dysplasias have been identified and may be classified into several general categories: 1) qualitative or quantitative abnormalities in the structural proteins of cartilage; 2) inborn errors of cartilage metabolism; 3) defects in local regulators of cartilage growth; and 4) systemic defects influencing cartilage development.