Elastin, the protein responsible for the elastic properties of vertebrate t
issues, has been thought to be solely restricted to that role. As a consequ
ence, elastin was conventionally described as an amorphous polymer. Recent
results in the biomedical, biochemical and biophysical fields have lead to
the conclusion that the presence of elastin in the extracellular space has
very complex implications involving many other molecules. The present revie
w describes the current state of knowledge concerning elastin as an elastic
macromolecule. First, the genetic. biological, biochemical and biophysical
processes leading to a functional polymer are described. Second, the elast
ic function of elastin is discussed. The controversy on elastin structure a
nd elasticity is discussed and a novel dynamic mechanism of elasticity prop
osed. Finally, pathologies where the elastin molecule is involved are consi
dered. This updated description of functional elastin provides the required
background for the understanding of its pathologies and defines clearly th
e properties a substance should possess to be qualified as a good elastic b
iomaterial. (C) 1999 Elsevier Science Ltd. All lights reserved.