Collagen Type IX Alpha 1 (COL9a1)

COL9a1 is one of the three alpha chains of type IX collagen, the major 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 this gene may be associated with multiple epiphyseal dysplasia. Defects in COL9A1 are the cause of Stickler syndrome autosomal recessive COL9A1-related. COL9A1ARSTL is an autosomal recessive form of Stickler syndrome, an inherited disorder that associates ocular signs with more or less complete forms of Pierre Robin sequence, bone disorders and sensorineural deafness.