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URL of this page: https://medlineplus.gov/genetics/gene/col4a5/

COL4A5 gene

collagen type IV alpha 5 chain

Normal Function

The COL4A5 gene provides instructions for making one piece of a protein called collagen IV. Specifically, this gene makes the alpha5(IV) chain of collagen IV. This chain combines with two other types of alpha (IV) chains (the alpha3 and alpha4 chains) to make alpha345(IV) collagen molecules. These molecules attach to each other to form complex protein networks that make up a large portion of basement membranes, which are thin, sheet-like structures that separate and support cells in many tissues. Alpha345(IV) collagen networks play an especially important role in the basement membranes of the kidney, inner ear, and eye.

Health Conditions Related to Genetic Changes

Alport syndrome

Many variants (also called mutations) in the COL4A5 gene can cause Alport syndrome, a condition characterized by kidney disease, hearing loss, and eye abnormalities. Most of these variants change single protein building blocks (amino acids) in a region where the alpha5(IV) collagen chain combines with other collagen IV chains. Other variants in the COL4A5 gene severely decrease or prevent the production of alpha5(IV) chains. 

These changes in the structure or amount of alpha5(IV) chains severely impair the formation of alpha345(IV) collagen networks in the basement membranes of the kidney, inner ear, and eye. In the kidney, other types of collagen build up in the basement membranes, eventually scarring the kidneys and leading to kidney failure. Variants in this gene can also lead to hearing loss and changes in the lens of the eye and the light-sensitive tissue at the back of the eye (retina).

More About This Health Condition

Other Names for This Gene

  • ASLN
  • ATS
  • CA54
  • CO4A5_HUMAN
  • collagen IV, alpha-5 polypeptide
  • collagen of basement membrane, alpha-5 chain
  • collagen type IV alpha 5
  • collagen, type IV, alpha 5
  • collagen, type IV, alpha 5 (Alport syndrome)

Additional Information & Resources

Tests Listed in the Genetic Testing Registry

Scientific Articles on PubMed

Catalog of Genes and Diseases from OMIM

Gene and Variant Databases

References

  • Gross O, Netzer KO, Lambrecht R, Seibold S, Weber M. Meta-analysis of genotype-phenotype correlation in X-linked Alport syndrome: impact on clinical counselling. Nephrol Dial Transplant. 2002 Jul;17(7):1218-27. doi: 10.1093/ndt/17.7.1218. Citation on PubMed
  • Jais JP, Knebelmann B, Giatras I, De Marchi M, Rizzoni G, Renieri A, Weber M, Gross O, Netzer KO, Flinter F, Pirson Y, Dahan K, Wieslander J, Persson U, Tryggvason K, Martin P, Hertz JM, Schroder C, Sanak M, Carvalho MF, Saus J, Antignac C, Smeets H, Gubler MC. X-linked Alport syndrome: natural history and genotype-phenotype correlations in girls and women belonging to 195 families: a "European Community Alport Syndrome Concerted Action" study. J Am Soc Nephrol. 2003 Oct;14(10):2603-10. doi: 10.1097/01.asn.0000090034.71205.74. Citation on PubMed
  • Jais JP, Knebelmann B, Giatras I, Marchi M, Rizzoni G, Renieri A, Weber M, Gross O, Netzer KO, Flinter F, Pirson Y, Verellen C, Wieslander J, Persson U, Tryggvason K, Martin P, Hertz JM, Schroder C, Sanak M, Krejcova S, Carvalho MF, Saus J, Antignac C, Smeets H, Gubler MC. X-linked Alport syndrome: natural history in 195 families and genotype- phenotype correlations in males. J Am Soc Nephrol. 2000 Apr;11(4):649-657. doi: 10.1681/ASN.V114649. Citation on PubMed
  • Kashtan CE. Alport syndrome. An inherited disorder of renal, ocular, and cochlear basement membranes. Medicine (Baltimore). 1999 Sep;78(5):338-60. doi: 10.1097/00005792-199909000-00005. Citation on PubMed
  • Kashtan CE. Familial hematuria due to type IV collagen mutations: Alport syndrome and thin basement membrane nephropathy. Curr Opin Pediatr. 2004 Apr;16(2):177-81. doi: 10.1097/00008480-200404000-00011. Citation on PubMed
  • Nozu K, Yamamura T, Horinouchi T. Alport Syndrome. 2001 Aug 28 [updated 2025 Feb 27]. In: Adam MP, Feldman J, Mirzaa GM, Pagon RA, Wallace SE, Amemiya A, editors. GeneReviews(R) [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2025. Available from http://www.ncbi.nlm.nih.gov/books/NBK1207/ Citation on PubMed
  • Pescucci C, Longo I, Bruttini M, Mari F, Renieri A. Type-IV collagen related diseases. J Nephrol. 2003 Mar-Apr;16(2):314-6. Citation on PubMed
  • Slajpah M, Gorinsek B, Berginc G, Vizjak A, Ferluga D, Hvala A, Meglic A, Jaksa I, Furlan P, Gregoric A, Kaplan-Pavlovcic S, Ravnik-Glavac M, Glavac D. Sixteen novel mutations identified in COL4A3, COL4A4, and COL4A5 genes in Slovenian families with Alport syndrome and benign familial hematuria. Kidney Int. 2007 Jun;71(12):1287-95. doi: 10.1038/sj.ki.5002221. Epub 2007 Mar 28. Citation on PubMed

The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.