COL11A2

COL11A2

COL11A2 is a gene that encodes the alpha-2 chain of type XI collagen, a minor fibrillar collagen found in the extracellular matrix of various tissues. This gene plays a crucial role in the development and maintenance of cartilage and other connective tissues.

Structure

The COL11A2 gene is located on chromosome 6p21.3 and consists of 67 exons. The protein product of COL11A2 is a component of type XI collagen, which is a heterotrimer composed of alpha-1(XI), alpha-2(XI), and alpha-3(XI) chains. Type XI collagen is closely associated with type II collagen in the cartilage matrix, where it helps regulate the diameter of collagen fibrils and maintain the integrity of the cartilage.

Function

Type XI collagen, including the alpha-2 chain encoded by COL11A2, is essential for the normal formation of cartilage and the proper development of the skeletal system. It is involved in the assembly of collagen fibrils, which provide structural support to tissues. Mutations in COL11A2 can disrupt this process, leading to various skeletal and connective tissue disorders.

Clinical Significance

Mutations in the COL11A2 gene are associated with several genetic disorders, including:

• Stickler syndrome type 3: A condition characterized by distinctive facial features, eye abnormalities, hearing loss, and joint problems. Unlike other types of Stickler syndrome, type 3 does not typically involve eye problems.

• Otospondylomegaepiphyseal dysplasia (OSMED): A rare disorder that affects bone growth, leading to short stature, hearing loss, and distinctive facial features.

• Nonsyndromic hearing loss: Some mutations in COL11A2 are linked to autosomal dominant or recessive forms of hearing loss without other associated symptoms.

Genetic Testing and Diagnosis

Genetic testing for mutations in the COL11A2 gene can confirm a diagnosis of related disorders. This is particularly useful for distinguishing between different types of Stickler syndrome and other connective tissue disorders. Early diagnosis can help manage symptoms and improve quality of life for affected individuals.

Research and Future Directions

Ongoing research is focused on understanding the precise role of COL11A2 in cartilage development and its interactions with other collagen types. Advances in genetic and molecular techniques may lead to improved diagnostic methods and potential therapies for conditions associated with COL11A2 mutations.

See Also

• Collagen
• Connective tissue
• Genetic disorders

External Links

• Genetics Home Reference: COL11A2
• OMIM Entry on COL11A2