A large number of extracellular matrix proteins have been found to contain variations of the epidermal growth factor (EGF) domain and have been implicated in functions as diverse as blood coagulation, activation of complement and determination of cell fate during development. FBLN4 contains four EGF2 domains and six calcium-binding EGF2 domains. This gene is necessary for elastic fiber formation and connective tissue development. Defects in this gene are cause of an autosomal recessive cutis laxa syndrome.EFEMP1 is likewise expressed in a wide range of adult and fetal tissues. In contrast to EFEMP1, however, EFEMP2 was not significantly overexpressed in senescent or quiescent fibroblasts, suggesting a diversity of function within this EGF-like domain subfamily.