2uur

Structural highlights

Disease

[CO9A1_HUMAN] Defects in COL9A1 are the cause of multiple epiphyseal dysplasia type 6 (EDM6) [MIM:614135]. A generalized skeletal dysplasia associated with significant morbidity. Joint pain, joint deformity, waddling gait, and short stature are the main clinical signs and symptoms. Radiological examination of the skeleton shows delayed, irregular mineralization of the epiphyseal ossification centers and of the centers of the carpal and tarsal bones. Multiple epiphyseal dysplasia is broadly categorized into the more severe Fairbank and the milder Ribbing types. The Fairbank type is characterized by shortness of stature, short and stubby fingers, small epiphyses in several joints, including the knee, ankle, hand, and hip. The Ribbing type is confined predominantly to the hip joints and is characterized by hands that are normal and stature that is normal or near-normal.^[1] Defects in COL9A1 are the cause of Stickler syndrome type 4 (STL4) [MIM:614134]. 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. Ocular disorders may include juvenile cataract, myopia, strabismus, vitreoretinal or chorioretinal degeneration, retinal detachment, and chronic uveitis. Robin sequence includes an opening in the roof of the mouth (a cleft palate), a large tongue (macroglossia), and a small lower jaw (micrognathia). Bones are affected by slight platyspondylisis and large, often defective epiphyses. Juvenile joint laxity is followed by early signs of arthrosis. The degree of hearing loss varies among affected individuals and may become more severe over time. Syndrome expressivity is variable.^[2]

Function

[CO9A1_HUMAN] Structural component of hyaline cartilage and vitreous of the eye.

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

See Also

• Collagen

References

1. ↑ Czarny-Ratajczak M, Lohiniva J, Rogala P, Kozlowski K, Perala M, Carter L, Spector TD, Kolodziej L, Seppanen U, Glazar R, Krolewski J, Latos-Bielenska A, Ala-Kokko L. A mutation in COL9A1 causes multiple epiphyseal dysplasia: further evidence for locus heterogeneity. Am J Hum Genet. 2001 Nov;69(5):969-80. Epub 2001 Sep 14. PMID:11565064 doi:10.1086/324023
2. ↑ Van Camp G, Snoeckx RL, Hilgert N, van den Ende J, Fukuoka H, Wagatsuma M, Suzuki H, Smets RM, Vanhoenacker F, Declau F, Van de Heyning P, Usami S. A new autosomal recessive form of Stickler syndrome is caused by a mutation in the COL9A1 gene. Am J Hum Genet. 2006 Sep;79(3):449-57. Epub 2006 Jun 26. PMID:16909383 doi:10.1086/506478
3. ↑ Leppanen VM, Tossavainen H, Permi P, Lehtio L, Ronnholm G, Goldman A, Kilpelainen I, Pihlajamaa T. Crystal structure of the N-terminal NC4 domain of collagen IX, a zinc binding member of the laminin-neurexin-sex hormone binding globulin (LNS) domain family. J Biol Chem. 2007 Aug 10;282(32):23219-30. Epub 2007 Jun 6. PMID:17553797 doi:M702514200