collagen type ix


Summary: A fibril-associated collagen usually found crosslinked to the surface of COLLAGEN TYPE II fibrils. It is a heterotrimer containing alpha1(IX), alpha2(IX) and alpha3(IX) subunits.

Top Publications

  1. Paassilta P, Lohiniva J, Annunen S, Bonaventure J, Le Merrer M, Pai L, et al. COL9A3: A third locus for multiple epiphyseal dysplasia. Am J Hum Genet. 1999;64:1036-44 pubmed
    ..This is the first disease-causing mutation identified in COL9A3. Our results also show that COL9A3, located on chromosome 20, is a third locus for MED. ..
  2. Solovieva S, Lohiniva J, Leino Arjas P, Raininko R, Luoma K, Ala Kokko L, et al. Intervertebral disc degeneration in relation to the COL9A3 and the IL-1ss gene polymorphisms. Eur Spine J. 2006;15:613-9 pubmed
    ..1, 95% CI 1.0-4.2) as compared with non-carriers. The results suggest that the effect of the COL9A3 gene polymorphism on DD might be modified by the IL-1beta gene polymorphism. ..
  3. Alizadeh B, Njajou O, Bijkerk C, Meulenbelt I, Wildt S, Hofman A, et al. Evidence for a role of the genomic region of the gene encoding for the alpha1 chain of type IX collagen (COL9A1) in hip osteoarthritis: A population-based study. Arthritis Rheum. 2005;52:1437-42 pubmed
    ..01) from that in controls. Our data suggest that susceptibility for hip OA is conferred within or close to the COL9A1 gene in linkage disequilibrium with the COL9A1 509-8B2 marker. ..
  4. Nakashima E, Ikegawa S, Ohashi H, Kimizuka M, Nishimura G. Double-layered patella in multiple epiphyseal dysplasia is not exclusive to DTDST mutation. Am J Med Genet A. 2005;133A:106-7 pubmed
  5. Jakkula E, Lohiniva J, Capone A, Bonafe L, Marti M, Schuster V, et al. A recurrent R718W mutation in COMP results in multiple epiphyseal dysplasia with mild myopathy: clinical and pathogenetic overlap with collagen IX mutations. J Med Genet. 2003;40:942-8 pubmed
  6. Eyre D, Pietka T, Weis M, Wu J. Covalent cross-linking of the NC1 domain of collagen type IX to collagen type II in cartilage. J Biol Chem. 2004;279:2568-74 pubmed
  7. Itoh T, Shirahama S, Nakashima E, Maeda K, Haga N, Kitoh H, et al. Comprehensive screening of multiple epiphyseal dysplasia mutations in Japanese population. Am J Med Genet A. 2006;140:1280-4 pubmed
    ..Based on the integration of clinical and genetic information, we propose an algorithm for detecting mutations in Japanese MED patients. Our study further supports the existence of additional MED gene(s). ..
  8. Higashino K, Matsui Y, Yagi S, Takata Y, Goto T, Sakai T, et al. The alpha2 type IX collagen tryptophan polymorphism is associated with the severity of disc degeneration in younger patients with herniated nucleus pulposus of the lumbar spine. Int Orthop. 2007;31:107-11 pubmed
    ..Our results suggest that the Trp2 allele is an age-dependent risk factor for the severity of disc degeneration in younger patients with symptomatic herniated nucleus pulposus of the lumbar spine. ..
  9. Jim J, Noponen Hietala N, Cheung K, Ott J, Karppinen J, Sahraravand A, et al. The TRP2 allele of COL9A2 is an age-dependent risk factor for the development and severity of intervertebral disc degeneration. Spine (Phila Pa 1976). 2005;30:2735-42 pubmed
    ..The contrasting Trp allele frequencies between the Finns and the Chinese are the first indication that the genetic risk factors for DDD varies between ethnic groups. ..

More Information


  1. Jakkula E, Makitie O, Czarny Ratajczak M, Czarny Ratacjzak M, Jackson G, Damignani R, et al. Mutations in the known genes are not the major cause of MED; distinctive phenotypic entities among patients with no identified mutations. Eur J Hum Genet. 2005;13:292-301 pubmed
    ..The existence of additional MED loci is supported by the exclusion of known loci by mutation analysis and finding of specific subgroups among these patients. ..
  2. Gartaganis S, Georgakopoulos C, Assouti M, Mela E, Exarchou A, Giannelou I, et al. Changes in HNK-1 epitope and collagen type IX in the aqueous humour of patients with pseudoexfoliation syndrome. Curr Eye Res. 2004;28:5-10 pubmed
    ..Protein and IgG were quantified densitometrically after their electrophoretic separation. Collagen type IX, 3-sulphoglucuronic acid (HNK-1 epitope), biglycan and heparan sulphate proteoglycans were detected in ..
  3. Karppinen J, Paakko E, Paassilta P, Lohiniva J, Kurunlahti M, Tervonen O, et al. Radiologic phenotypes in lumbar MR imaging for a gene defect in the COL9A3 gene of type IX collagen. Radiology. 2003;227:143-8 pubmed
    ..The results of this study indicate that the presence of Trp3 allele is associated with Scheuermann disease and intervertebral disk degeneration. No associations were found for other radiologic phenotypes. ..
  4. Fiedler J, Stove J, Heber F, Brenner R. Clinical phenotype and molecular diagnosis of multiple epiphyseal dysplasia with relative hip sparing during childhood (EDM2). Am J Med Genet. 2002;112:144-53 pubmed
    ..results indicate that mutations leading to skipping of exon 3 within the COL3 domain of the alpha2-chain of collagen type IX may be relatively common in patients with a special subtype of multiple epiphyseal dysplasia (MED) in which ..
  5. Annunen S, Paassilta P, Lohiniva J, Perala M, Pihlajamaa T, Karppinen J, et al. An allele of COL9A2 associated with intervertebral disc disease. Science. 1999;285:409-12 pubmed
    ..5, and subsequent linkage disequilibrium analysis conditional on linkage gave an additional lod score of 7.1. ..
  6. Paassilta P, Lohiniva J, Göring H, Perala M, Räinä S, Karppinen J, et al. Identification of a novel common genetic risk factor for lumbar disk disease. JAMA. 2001;285:1843-9 pubmed
    ..Presence of at least 1 Trp3 allele increases risk of LDD about 3-fold. This study led to the identification of a novel common genetic risk factor for LDD, confirming that genetic risk factors likely play a significant role in LDD. ..
  7. Unger S, Bonafe L, Superti Furga A. Multiple epiphyseal dysplasia: clinical and radiographic features, differential diagnosis and molecular basis. Best Pract Res Clin Rheumatol. 2008;22:19-32 pubmed publisher
    ..Mutations in at least six different genes can cause multiple epiphyseal dysplasia, and it can be either dominant or recessive. Molecular diagnosis is important for accurate prognosis and genetic counselling...
  8. Näkki A, Videman T, Kujala U, Suhonen M, Männikkö M, Peltonen L, et al. Candidate gene association study of magnetic resonance imaging-based hip osteoarthritis (OA): evidence for COL9A2 gene as a common predisposing factor for hip OA and lumbar disc degeneration. J Rheumatol. 2011;38:747-52 pubmed publisher
    ..002) genes showed association with hip OA. The associating G allele in COL9A2 changes a glutamine to arginine or to tryptophan and may predispose to both hip OA and LDD, making it a candidate for degenerative connective tissue diseases. ..
  9. Lachman R, Krakow D, Cohn D, Rimoin D. MED, COMP, multilayered and NEIN: an overview of multiple epiphyseal dysplasia. Pediatr Radiol. 2005;35:116-23 pubmed
    ..This review will include the mechanics of diagnostic and molecular triage for these disorders. ..
  10. Assouti M, Vynios D, Anagnostides S, Papadopoulos G, Georgakopoulos C, Gartaganis S. Collagen type IX and HNK-1 epitope in tears of patients with pseudoexfoliation syndrome. Biochim Biophys Acta. 2006;1762:54-8 pubmed
    ..e., cardiovascular tissue, skin, and still lacks elucidated pathogenesis. Collagen type IX and HNK-1 epitope have been considered characteristic constituents of the aqueous humour of PEX patients, ..
  11. Seki S, Kawaguchi Y, Mori M, Mio F, Chiba K, Mikami Y, et al. Association study of COL9A2 with lumbar disc disease in the Japanese population. J Hum Genet. 2006;51:1063-7 pubmed
    ..011). Thus, the association of Trp2 with LDD was not replicated, but COL9A2 susceptibility allele(s) other than Trp2 may be present in Japanese LDD. ..
  12. Dreier R, Opolka A, Grifka J, Bruckner P, Grassel S. Collagen IX-deficiency seriously compromises growth cartilage development in mice. Matrix Biol. 2008;27:319-29 pubmed publisher
    ..As a result, all long bones are shorter and broader in newborn Col9a1-/- mice. Remarkably, these abnormalities are attenuated in adult mice, but the number of cells per area still is too low due to reduced cell proliferation. ..
  13. Kapyla J, Jäälinoja J, Tulla M, Ylostalo J, Nissinen L, Viitasalo T, et al. The fibril-associated collagen IX provides a novel mechanism for cell adhesion to cartilaginous matrix. J Biol Chem. 2004;279:51677-87 pubmed
    ..Thus, our results indicate that collagen IX has unique cell adhesion properties when compared with other collagens, and it provides a novel mechanism for cell adhesion to cartilaginous matrix. ..
  14. Briggs M, Chapman K. Pseudoachondroplasia and multiple epiphyseal dysplasia: mutation review, molecular interactions, and genotype to phenotype correlations. Hum Mutat. 2002;19:465-78 pubmed
  15. Zhang P, Jimenez S, Stokes D. Regulation of human COL9A1 gene expression. Activation of the proximal promoter region by SOX9. J Biol Chem. 2003;278:117-23 pubmed
    ..DNA-protein binding assays and super-shift analysis revealed that SOX9 can form a specific complex with one of the SOX/Sry-binding sites with in the -560 to +130 region. ..
  16. Solovieva S, Lohiniva J, Leino Arjas P, Raininko R, Luoma K, Ala Kokko L, et al. COL9A3 gene polymorphism and obesity in intervertebral disc degeneration of the lumbar spine: evidence of gene-environment interaction. Spine (Phila Pa 1976). 2002;27:2691-6 pubmed
    ..The effect of obesity on lumbar disc degeneration seems to be modified by the collagen IX gene polymorphism, so that people who carry the Trp3 allele are at increased risk if they are persistently obese. ..
  17. Genzer M, Bridgewater L. A Col9a1 enhancer element activated by two interdependent SOX9 dimers. Nucleic Acids Res. 2007;35:1178-86 pubmed
  18. Fresquet M, Jowitt T, Ylostalo J, Coffey P, Meadows R, Ala Kokko L, et al. Structural and functional characterization of recombinant matrilin-3 A-domain and implications for human genetic bone diseases. J Biol Chem. 2007;282:34634-43 pubmed
    ..Furthermore, we have also determined that the matrilin-3 A-domain appears to bind exclusively to the COL3 domain of type IX collagen and that this binding is abolished in the presence of a disease causing mutation in type IX collagen. ..
  19. Kales S, Linos A, Chatzis C, Sai Y, Halla M, Nasioulas G, et al. The role of collagen IX tryptophan polymorphisms in symptomatic intervertebral disc disease in Southern European patients. Spine (Phila Pa 1976). 2004;29:1266-70 pubmed
    ..The 2 previously described Trp alleles in COL9A2 and COL9A3 are likely to be less significant susceptibility factors for intervertebral disc disease development in Southern European populations. ..
  20. Jackson G, Marcus Soekarman D, Stolte Dijkstra I, Verrips A, Taylor J, Briggs M. Type IX collagen gene mutations can result in multiple epiphyseal dysplasia that is associated with osteochondritis dissecans and a mild myopathy. Am J Med Genet A. 2010;152A:863-9 pubmed publisher
    ..This study therefore extends the range of gene-mutations that can cause MED-related myopathy. (c) 2010 Wiley-Liss, Inc. ..
  21. Nakashima E, Kitoh H, Maeda K, Haga N, Kosaki R, Mabuchi A, et al. Novel COL9A3 mutation in a family with multiple epiphyseal dysplasia. Am J Med Genet A. 2005;132A:181-4 pubmed
    ..The radiographic phenotypes of the patients were relatively milder than those of previously reported cases, and were indistinguishable to common, idiopathic OA. ..
  22. Takahashi M, Matsui Y, Goto T, Nishimura G, Ikegawa S, Ohashi H, et al. Intrafamilial phenotypic diversity in multiple epiphyseal dysplasia associated with a COL9A2 mutation (EDM2). Clin Rheumatol. 2006;25:591-5 pubmed
  23. Hu K, Xu L, Cao L, Flahiff C, Brussiau J, Ho K, et al. Pathogenesis of osteoarthritis-like changes in the joints of mice deficient in type IX collagen. Arthritis Rheum. 2006;54:2891-900 pubmed
    ..All of these changes occurred only at medial sites. Lack of type IX collagen in Col9a1-/- mice results in age-dependent OA-like changes in the knee joints and TMJs. ..
  24. Jäälinoja J, Nissilä M, Kauppi M, Hakala M, Laiho K, Karttunen R, et al. Serum antibodies against intact human collagen IX are elevated at onset of rheumatoid arthritis but are not related to development of erosions. J Rheumatol. 2008;35:745-51 pubmed
    ..These autoantibodies were observed already at the early stages of the disease, which may reflect their diagnostic potential in RA. ..
  25. Fu P, Cong R, Chen S, Zhang L, Ding Z, Zhou Q, et al. [CONDITIONS OF SYNOVIAL MESENCHYMAL STEM CELLS DIFFERENTIATING INTO FIBROCARTILAGE CELLS]. Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2015;29:81-91 pubmed
    ..Y (SRY)-box 9 gene (Sox9), aggrecan gene (AGN), collagen type I gene (Col I), collagen type II gene (Col II), collagen type IX gene (Col IX) were used for result confirmation...
  26. Fitch J, Kidder J, Linsenmayer T. Cellular invasion of the chicken corneal stroma during development: regulation by multiple matrix metalloproteases and the lens. Dev Dyn. 2005;232:106-18 pubmed
    ..This block, which seems to influence invasive behavior independently of matrix modification, is a transient event that is released in ovo just before invasion proceeds. ..
  27. Kitamoto J, Hyer J. The expression of Wnt2b in the optic cup lip requires a border between the pigmented and nonpigmented epithelium. Mol Vis. 2010;16:2701-17 pubmed
  28. Aladin D, Cheung K, Chan D, Yee A, Jim J, Luk K, et al. Expression of the Trp2 allele of COL9A2 is associated with alterations in the mechanical properties of human intervertebral discs. Spine (Phila Pa 1976). 2007;32:2820-6 pubmed publisher
    ..This is the first study to demonstrate an association between the Trp2 allele and disc mechanics, thus relating genetic variations and debilitating mechanical alterations that may ultimately result in intervertebral disc degeneration. ..
  29. Blumbach K, Niehoff A, Paulsson M, Zaucke F. Ablation of collagen IX and COMP disrupts epiphyseal cartilage architecture. Matrix Biol. 2008;27:306-18 pubmed publisher
    ..The contribution of COMP to the phenotype of mice deficient in both collagen IX and COMP appears minor, even though clear differences in the deposition of matrilin-3 were detected. ..
  30. Boudko S, Bachinger H. The NC2 domain of type IX collagen determines the chain register of the triple helix. J Biol Chem. 2012;287:44536-45 pubmed publisher
    ..Differences in thermal stability and binding to the A3 domain unambiguously demonstrate that the NC2 domain of type IX collagen determines not only the chain composition but also the chain register of the adjacent triple helix. ..
  31. Sivakumaran T, Resendes B, Robertson N, Giersch A, Morton C. Characterization of an abundant COL9A1 transcript in the cochlea with a novel 3' UTR: Expression studies and detection of miRNA target sequence. J Assoc Res Otolaryngol. 2006;7:160-72 pubmed
  32. Akkiraju H, Srinivasan P, Xu X, Jia X, Safran C, Nohe A. CK2.1, a bone morphogenetic protein receptor type Ia mimetic peptide, repairs cartilage in mice with destabilized medial meniscus. Stem Cell Res Ther. 2017;8:82 pubmed publisher
    ..Immunofluorescence analysis revealed collagen type IX production along with collagen type II in the AC of mice injected with HGP-CK2.1...
  33. Matsui Y. [Type IX collagen diseases]. Clin Calcium. 2006;16:1894-8 pubmed
    ..Polymorphic variants of the type IX collagen genes are associated with lumbar disc diseases. It is getting more important to understand the biological roles of collagen IX in the musculoskeletal system. ..
  34. Kolettas E, Muir H, Barrett J, Hardingham T. Chondrocyte phenotype and cell survival are regulated by culture conditions and by specific cytokines through the expression of Sox-9 transcription factor. Rheumatology (Oxford). 2001;40:1146-56 pubmed
    ..As Sox-9 appears to be essential for matrix production, the potent effect of IL-1alpha in suppressing Sox-9 expression may limit the ability of cartilage to repair during inflammatory joint diseases. ..
  35. Jackson G, Mittaz Crettol L, Taylor J, Mortier G, Spranger J, Zabel B, et al. Pseudoachondroplasia and multiple epiphyseal dysplasia: a 7-year comprehensive analysis of the known disease genes identify novel and recurrent mutations and provides an accurate assessment of their relative contribution. Hum Mutat. 2012;33:144-57 pubmed publisher
    ..Furthermore, this study provides the first indication of the relative contribution of each gene and confirms that they account for the majority of PSACH and MED. ..
  36. Stolz M, Gottardi R, Raiteri R, Miot S, Martin I, Imer R, et al. Early detection of aging cartilage and osteoarthritis in mice and patient samples using atomic force microscopy. Nat Nanotechnol. 2009;4:186-92 pubmed publisher
    ..Indentation-type atomic force microscopy may potentially be developed into a minimally invasive arthroscopic tool to diagnose the early onset of osteoarthritis in situ. ..
  37. Savontaus M, Rintala Jämsä M, Morko J, Ronning O, Metsaranta M, Vuorio E. Abnormal craniofacial development and expression patterns of extracellular matrix components in transgenic Del1 mice harboring a deletion mutation in the type II collagen gene. Orthod Craniofac Res. 2004;7:216-26 pubmed
    ..In addition to affecting endochondral ossification, the type II collagen mutation also disturbs intramembranous ossification in the developing craniofacial skeleton. ..
  38. Xi Y, Hu Y, Lu Z, Zheng H, Chen Y, Qi Z. Gene expression of collagen types IX and X in the lumbar disc. Chin J Traumatol. 2004;7:76-80 pubmed
    ..Results of type X collagen expression suggest that type X collagen is expressed only in older adult and senile discs (i.e., when disc degeneration has already reached a terminal stage), indicating the terminal stage of degeneration. ..
  39. Brachvogel B, Zaucke F, Dave K, Norris E, Stermann J, Dayakli M, et al. Comparative proteomic analysis of normal and collagen IX null mouse cartilage reveals altered extracellular matrix composition and novel components of the collagen IX interactome. J Biol Chem. 2013;288:13481-92 pubmed publisher
    ..Collagen IX is an integral cartilage extracellular matrix component important in skeletal development and joint function...
  40. Rezai Rad M, Wise G, Brooks H, Flanagan M, Yao S. Activation of proliferation and differentiation of dental follicle stem cells (DFSCs) by heat stress. Cell Prolif. 2013;46:58-66 pubmed publisher
  41. Wu J, Eyre D. Intervertebral disc collagen. Usage of the short form of the alpha1(IX) chain in bovine nucleus pulposus. J Biol Chem. 2003;278:24521-5 pubmed
    ..As in cartilage, type IX collagen of nucleus pulposus was heavily cross-linked to type II collagen and to other molecules of type IX collagen with a similar site occupancy. ..
  42. Farjanel J, Schurmann G, Bruckner P. Contacts with fibrils containing collagen I, but not collagens II, IX, and XI, can destabilize the cartilage phenotype of chondrocytes. Osteoarthritis Cartilage. 2001;9 Suppl A:S55-63 pubmed
    ..g., articular cartilage. If pathologically altered matrix suprastructures lead to a dysregulation of collagen production also in vivo compromised cartilage functions inevitably will be propagated further. ..
  43. Unger S, Hecht J. Pseudoachondroplasia and multiple epiphyseal dysplasia: New etiologic developments. Am J Med Genet. 2001;106:244-50 pubmed
    ..This article reviews the clinical features of PSACH and MED, the known mutations, and the pathogenetic effect of COMP mutations on the cartilage extracellular matrix...
  44. Wang C, Iida K, Egusa H, Hokugo A, Jewett A, Nishimura I. Trabecular bone deterioration in col9a1+/- mice associated with enlarged osteoclasts adhered to collagen IX-deficient bone. J Bone Miner Res. 2008;23:837-49 pubmed publisher
    ..The data suggest the involvement of bone collagen IX in the pathogenesis of osteoporosis. ..
  45. Aszodi A, Hunziker E, Olsen B, Fassler R. The role of collagen II and cartilage fibril-associated molecules in skeletal development. Osteoarthritis Cartilage. 2001;9 Suppl A:S150-9 pubmed
    ..Collagen II is important for cartilage formation, collagen IX for cartilage maintenance and matrilin-1 is redundant. ..
  46. Baker S, Booth C, Fillman C, Shapiro M, Blair M, Hyland J, et al. A loss of function mutation in the COL9A2 gene causes autosomal recessive Stickler syndrome. Am J Med Genet A. 2011;155A:1668-72 pubmed publisher
    ..Together the data from the present study and the previous studies suggest that loss-of-function mutations in any of the collagen IX genes can cause autosomal recessive Stickler syndrome. ..
  47. Danfelter M, Onnerfjord P, Heinegard D. Fragmentation of proteins in cartilage treated with interleukin-1: specific cleavage of type IX collagen by matrix metalloproteinase 13 releases the NC4 domain. J Biol Chem. 2007;282:36933-41 pubmed
    ..These data describe cleavage by an MMP-13 activity toward non-collagenous and triple helix domains. These potentially important degradation events precede the major loss of type II collagen. ..
  48. Posey K, Hankenson K, Veerisetty A, Bornstein P, Lawler J, Hecht J. Skeletal abnormalities in mice lacking extracellular matrix proteins, thrombospondin-1, thrombospondin-3, thrombospondin-5, and type IX collagen. Am J Pathol. 2008;172:1664-74 pubmed publisher
  49. Ikeda T, Mabuchi A, Fukuda A, Kawakami A, Ryo Y, Yamamoto S, et al. Association analysis of single nucleotide polymorphisms in cartilage-specific collagen genes with knee and hip osteoarthritis in the Japanese population. J Bone Miner Res. 2002;17:1290-6 pubmed
    ..48). Haplotype analysis showed significant association between a specific haplotype of COL2A1 and hip OA (p = 0.024; OR = 1.30). Further analysis of these two genes will shed light on the molecular mechanisms of OA. ..
  50. Fresquet M, Jackson G, Loughlin J, Briggs M. Novel mutations in exon 2 of MATN3 affect residues within the alpha-helices of the A-domain and can result in the intracellular retention of mutant matrilin-3. Hum Mutat. 2008;29:330 pubmed publisher
    ..Therefore, despite extensive biochemical analysis the disease mechanism of p.Lys231Asn remains unresolved and care should be taken in counseling for these types of mutation in MATN3. ..
  51. Parsons P, Gilbert S, Vaughan Thomas A, Sorrell D, Notman R, Bishop M, et al. Type IX collagen interacts with fibronectin providing an important molecular bridge in articular cartilage. J Biol Chem. 2011;286:34986-97 pubmed publisher
    ..This novel interaction between the NC4 domain of type IX collagen and fibronectin may represent an in vivo interaction in cartilage that could contribute to the matrix integrity of the tissue. ..
  52. Ikegawa S. [Bone and joint diseases in children. Skeletal dysplasia in children--unrecognized cases in daily practice]. Clin Calcium. 2010;20:840-7 pubmed publisher
    ..The collect diagnosis would lead to better treatment and care for patients and families. ..
  53. Jung W, Balce G, Cho J, Jung S, Hong S, Song H. COMP and Col9A3 mutations and their relationship to the pseudoachondroplasia phenotype. Int J Mol Med. 2010;26:885-91 pubmed
    ..Col9A3 and gender play confounding roles in the phenotypic severity of PSACH. The presence of the PSACH phenotype in patients who tested negative for known mutations further confirms the genetic heterogeneity of this condition. ..
  54. Adkisson H, Martin J, Amendola R, Milliman C, Mauch K, Katwal A, et al. The potential of human allogeneic juvenile chondrocytes for restoration of articular cartilage. Am J Sports Med. 2010;38:1324-33 pubmed publisher
    ..Chondrocytes from juvenile cadaveric donors may represent an alternative to autologous cells. Hypothesis/..
  55. Asamura K, Abe S, Imamura Y, Aszodi A, Suzuki N, Hashimoto S, et al. Type IX collagen is crucial for normal hearing. Neuroscience. 2005;132:493-500 pubmed
    ..This study further confirmed, by means of real-time PCR, the presence of collagen type IX genes in the mouse inner ear...
  56. Polur I, Lee P, Servais J, Xu L, Li Y. Role of HTRA1, a serine protease, in the progression of articular cartilage degeneration. Histol Histopathol. 2010;25:599-608 pubmed publisher
    ..Results indicate that HtrA1 may disrupt the pericellular matrix network, resulting in alteration of chondrocyte metabolisms. This eventually leads to OA...
  57. Zaucke F, Grassel S. Genetic mouse models for the functional analysis of the perifibrillar components collagen IX, COMP and matrilin-3: Implications for growth cartilage differentiation and endochondral ossification. Histol Histopathol. 2009;24:1067-79 pubmed publisher
  58. George R, Smith T, Callaghan S, Hardman L, Pierides C, Horaitis O, et al. Response to Stenson et al on the review of general mutation databases. J Med Genet. 2008;45:319-20 pubmed
  59. Liu L, Jin C, Cao D, Zhao N, Lin C, Sun K. [Analysis of association between COL9A1 gene and idiopathic congenital talipes equinovarus]. Yi Chuan. 2007;29:427-32 pubmed
    ..05). Expression of COL9A1 on mRNA levels showed significantly higher in patients with ICTEV than in normal person (t=4.7500, P<0.05) . These results indicate that COL9A1 gene may be important suscept-ble genes of ICTEV. ..
  60. Vizzini A, Arizza V, Cervello M, Cammarata M, Gambino R, Parrinello N. Cloning and expression of a type IX-like collagen in tissues of the ascidian Ciona intestinalis. Biochim Biophys Acta. 2002;1577:38-44 pubmed
    ..64%, 48.95%) between the type IX-like collagen of C. intestinalis and mouse and human type IX collagen. In situ hybridization of tunic and pharynx tissues shows the presence of transcripts in connective tissue cells...
  61. Chen R, Gong B, Li Q, Zeng G, Hao F, Li N, et al. [Analysis of COL9A2 gene mutations in a Chinese Han population with pathological myopia]. Zhonghua Yi Xue Yi Chuan Xue Za Zhi. 2014;31:129-33 pubmed publisher
    ..Two novel mutations, c.143G>C in exon 2 and c.884G>A in exon 17 of the COL9A2 gene, may contribute to the development of pathological myopia. ..
  62. Lam N, Li Y, Waldman A, Brussiau J, Lee P, Olsen B, et al. Age-dependent increase of discoidin domain receptor 2 and matrix metalloproteinase 13 expression in temporomandibular joint cartilage of type IX and type XI collagen-deficient mice. Arch Oral Biol. 2007;52:579-84 pubmed
    ..We conclude that, similar to previous observations in knee joints, the overexpression of Ddr2 and Mmp-13 may be responsible for the OA-like change in TM joints in mutant mice. ..
  63. Ikegawa S, Ikeda T, Mabuchi A. Genetic analysis of osteoarthritis: toward identification of its susceptibility genes. J Orthop Sci. 2003;8:737-9 pubmed
  64. Mitchell R, Huitema L, Skinner R, Brunt L, Severn C, Schulte Merker S, et al. New tools for studying osteoarthritis genetics in zebrafish. Osteoarthritis Cartilage. 2013;21:269-78 pubmed publisher
    ..Moreover, the tools used demonstrate the utility of the zebrafish model for functional studies on genes identified as playing a role in OA. ..
  65. Nikopoulos K, Schrauwen I, Simon M, Collin R, Veckeneer M, Keymolen K, et al. Autosomal recessive Stickler syndrome in two families is caused by mutations in the COL9A1 gene. Invest Ophthalmol Vis Sci. 2011;52:4774-9 pubmed publisher
    ..To investigate COL9A1 in two families suggestive of autosomal recessive Stickler syndrome and to delineate the associated phenotype...
  66. Decramer S, Bascands J, Schanstra J. Non-invasive markers of ureteropelvic junction obstruction. World J Urol. 2007;25:457-65 pubmed
    ..Both strategies will be complementary and will hopefully replace in the near future the invasive follow-up of newborns with UPJ obstruction. ..
  67. Paassilta P, Pihlajamaa T, Annunen S, Brewton R, Wood B, Johnson C, et al. Complete sequence of the 23-kilobase human COL9A3 gene. Detection of Gly-X-Y triplet deletions that represent neutral variants. J Biol Chem. 1999;274:22469-75 pubmed
    ..The results suggest that the next noncollagenous domain (NC2) is capable of correcting the alignment of the alpha chains, and this ensures the formation of an in-register triple helix. ..
  68. Budde B, Blumbach K, Ylostalo J, Zaucke F, Ehlen H, Wagener R, et al. Altered integration of matrilin-3 into cartilage extracellular matrix in the absence of collagen IX. Mol Cell Biol. 2005;25:10465-78 pubmed
    ..Matrilin-3 can be considered as an interface component, capable of interconnecting macromolecular networks and mediating interactions between cartilage fibrils and the extrafibrillar matrix. ..
  69. Skandalis S, Theocharis D, Noulas A. Chondroitin sulphate proteoglycans in the vitreous gel of sheep and goat. Biomed Chromatogr. 2007;21:451-7 pubmed
    ..These findings showed that, firstly, the CS content and the hydrodynamic size of the CS chain and, secondly, the sulphation pattern of CS chains from versican and collagen IX in both sheep and goat vitreous gels are PG type-dependent. ..
  70. Virtanen I, Karppinen J, Taimela S, Ott J, Barral S, Kaikkonen K, et al. Occupational and genetic risk factors associated with intervertebral disc disease. Spine (Phila Pa 1976). 2007;32:1129-34 pubmed
    ..Of the independent genetic markers, IL1A -889T allele had strongest association with IDD-phenotype. ..
  71. Hyun S, Park B, Rhim S, Bae C, Lee J, Roh S, et al. A haplotype at the COL9A2 gene locus contributes to the genetic risk for lumbar spinal stenosis in the Korean population. Spine (Phila Pa 1976). 2011;36:1273-8 pubmed publisher
    ..However, the genetic functions of COL9A2 haplotypes in LSS remain to be determined. ..
  72. So C, Kaluarachchi K, Tam P, Cheah K. Impact of mutations of cartilage matrix genes on matrix structure, gene activity and chondrogenesis. Osteoarthritis Cartilage. 2001;9 Suppl A:S160-73 pubmed
  73. Thomopoulos S, Williams G, Gimbel J, Favata M, Soslowsky L. Variation of biomechanical, structural, and compositional properties along the tendon to bone insertion site. J Orthop Res. 2003;21:413-9 pubmed
    ..Thus, the tendon to bony insertion site varies dramatically along its length in terms of its viscoelastic properties, collagen structure, and extracellular matrix composition. ..
  74. Cecil D, Terkeltaub R. Arterial calcification is driven by RAGE in Enpp1-/- mice. J Vasc Res. 2011;48:227-35 pubmed publisher
    ..Cultured Enpp1-/- aortic explants have decreased P(i)-stimulated release of sRAGE, and RAGE promotes ectopic chondrogenic differentiation and arterial calcification in Enpp1-/- mice. ..
  75. Sharawy M, Ali A, Choi W. Experimental induction of anterior disk displacement of the rabbit craniomandibular joint: an immuno-electron microscopic study of collagen and proteoglycan occurrence in the condylar cartilage. J Oral Pathol Med. 2003;32:176-84 pubmed
    ..These alterations are consistent with loss of the shock absorber function of the cartilage and injury of the underlying bone. ..
  76. Mainil Varlet P, Rieser F, Grogan S, Mueller W, Saager C, Jakob R. Articular cartilage repair using a tissue-engineered cartilage-like implant: an animal study. Osteoarthritis Cartilage. 2001;9 Suppl A:S6-15 pubmed
    ..This initial result holds promise for the use of this unique bioreactor/tissue-engineered implant in humans. ..