The FLNA gene is a member of the Filamin (FLN) family, which includes three members: filamin A, filamin B and filamin C. The encoded filamin proteins show 60–80% homology over their entire sequence, except for the two hinge regions. These three proteins are widely expressed during development. The FLNA gene encodes an actin-binding protein called filamin A, which links actin filaments to membrane glycoproteins and crosslinks actin filaments. It plays a role in modeling the cytoskeleton allowing cell shape changes and migration. Filamin A also interacts with transmembrane receptor complexes, integrins, and second messengers. Defects in this protein have been associated with genetic diseases including FG syndrome, frontometaphyseal dysplasia, intestinal pseudo-obstruction, Melnick-Needles syndrome, otopalatodigital syndrome type 1 and 2, periventricular heterotopia, and X-linked cardiac valvular dysplasia.