Extracellular matrix protein 1 is an extracellular protein containing motifs with a cysteine pattern characteristic of the cysteine pattern of the ligand-binding "double-loop" domains of the albumin protein family. This gene maps outside of the epidermal differentiation complex (EDC), a cluster of three gene families involved in epidermal differentiation. Alternatively spliced transcript variants encoding distinct isoforms have been described.
Defects in ECM1 are the cause of lipoid proteinosis also known as lipoid proteinosis of Urbach and Wiethe or hyalinosis cutis et mucosae. LiP is a rare autosomal recessive disorder characterized by generalized thickening of skin, mucosae and certain viscera. Classical features include beaded eyelid papules and laryngeal infiltration leading to hoarseness.