The evidence that elastin is fundamentally different from collagen has been reviewed.
With this background, a new classification based on etiology and distribution has been introduced for the dermal elastoses (those diseases associated with increased elastic tissue staining).
Using the criteria which differentiate elastin from collagen, each of the elastoses has been evaluated. The elastotic fibers seen histologically in actinic elastosis and pseudoxanthoma elasticum are more characteristic of elastin than collagen.
J. GRAHAM SMITH. The Dermal Elastoses. Arch Dermatol. 1963;88(4):382–392. doi:10.1001/archderm.1963.01590220014002