COL9A1 is one of the three alpha chains of type IX collagen, which is a minor (5-20%) collagen component of hyaline cartilage. Type IX collagen is usually found in tissues containing type II collagen, a fibrillar collagen. Studies in knockout mice have shown that synthesis of the alpha 1 chain is essential for assembly of type IX collagen molecules, a heterotrimeric molecule, and that lack of type IX collagen is associated with early onset osteoarthritis. Mutations in the COL9A1 gene are associated with osteoarthritis in humans, with multiple epiphyseal dysplasia, 6, a form of chondrodysplasia, and with Stickler syndrome, a disease characterized by ophthalmic, orofacial, articular, and auditory defects.
Protein Aliases: alpha 1 type IX collagen; alpha-1(IX) collagen chain; cartilage-specific short collagen; Collagen alpha-1(IX) chain; collagen IX, alpha-1 polypeptide; collagen, type IX, alpha 1; procollagen, type IX, alpha 1
Gene Aliases: Col9a-1; COL9A1; DJ149L1.1.2; EDM6; MED; STL4
Molecular Function: extracellular matrix structural protein