Collagen Type XIX is an 1,142 amino acid protein encoded by the human gene COL19A1. Collagen Type XIX belongs to the fibril-associated collagens with interrupted helices (FACIT) family. Collagen Type XIX is thought to act as a cross-bridge between collagen fibrils and other extracellular matrix molecules. Collagen Type XIX is also believed to be involved in skeletal myogenesis in the developing esophagus. It may also play a role in organization of the pericellular matrix or the sphinteric smooth muscle. Collagen Type XIX is normally found as an oligomer, the subunits being disulfide-linked. Expression of Collagen Type XIX is mainly localized to vascular, neuronal, mesenchymal, and some epithelial basement membrane zones in umbilical cord.