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PAX2 gene

paired box 2

Normal Function

The PAX2 gene belongs to a family of genes that plays a critical role in the formation of tissues and organs during embryonic development. The members of the PAX gene family are also important for maintaining the normal function of certain cells after birth. To carry out these roles, the PAX genes provide instructions for making proteins that attach to specific areas of DNA and help control the activity (expression) of particular genes. On the basis of this action, PAX proteins are called transcription factors.

During embryonic development, the PAX2 gene provides instructions for producing a protein that is involved in the formation of the eyes, ears, brain and spinal cord (central nervous system), kidneys, urinary tract, and genital tract. After birth, the PAX2 protein is thought to protect against cell death during periods of cellular stress.

Health Conditions Related to Genetic Changes

Renal coloboma syndrome

More than 40 variants (also known as mutations) in the PAX2 gene have been found to cause renal coloboma syndrome. Most variants are specific to each affected family; however, one variant has been found in multiple affected individuals. This variant inserts one DNA building block (nucleotide) into the PAX2 gene (written as 619insG). Most variants occur in the region of the protein that attaches to DNA, impairing its function as a transcription factor. A lack of functional PAX2 protein disrupts the formation of certain tissues (particularly the kidneys and eyes) during embryonic development, causing the signs and symptoms of renal coloboma syndrome.

More About This Health Condition


MedlinePlus Genetics provides information about Coloboma

More About This Health Condition

Congenital anomalies of kidney and urinary tract

More than 20 variants in the PAX2 gene have been found in people with abnormalities of the kidneys and other structures of the urinary system but without the eye problems of renal coloboma syndrome (described above). The urinary system abnormalities vary in severity and are grouped together as congenital anomalies of kidney and urinary tract (CAKUT). The most severe CAKUT abnormalities can cause kidney damage and life-threatening kidney failure.

The effects of CAKUT-associated PAX2 gene variants are not fully understood, but it is likely that they impair the function of the PAX2 protein, disrupting formation of the kidneys and urinary system during embryonic development. It is unclear why only structures of the urinary system are affected in these individuals.

More About This Health Condition

Other disorders

PAX2 gene variants are also found in individuals with abnormalities of the optic nerve, which carries visual information from the eyes to the brain. These individuals do not have the kidney anomalies associated with renal coloboma syndrome (described above). As in renal coloboma syndrome, the PAX2 gene variants associated with eye abnormalities likely disrupt regulation of genes that help direct normal eye development. Researchers are working to understand why variants in this gene can affect different organ systems in different people.

Other Names for This Gene

  • paired box gene 2
  • paired box homeotic gene 2
  • paired box protein 2

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


  • Amiel J, Audollent S, Joly D, Dureau P, Salomon R, Tellier AL, Auge J, Bouissou F, Antignac C, Gubler MC, Eccles MR, Munnich A, Vekemans M, Lyonnet S, Attie-Bitach T. PAX2 mutations in renal-coloboma syndrome: mutational hotspot and germline mosaicism. Eur J Hum Genet. 2000 Nov;8(11):820-6. doi: 10.1038/sj.ejhg.5200539. Citation on PubMed
  • Bower M, Salomon R, Allanson J, Antignac C, Benedicenti F, Benetti E, Binenbaum G, Jensen UB, Cochat P, DeCramer S, Dixon J, Drouin R, Falk MJ, Feret H, Gise R, Hunter A, Johnson K, Kumar R, Lavocat MP, Martin L, Moriniere V, Mowat D, Murer L, Nguyen HT, Peretz-Amit G, Pierce E, Place E, Rodig N, Salerno A, Sastry S, Sato T, Sayer JA, Schaafsma GC, Shoemaker L, Stockton DW, Tan WH, Tenconi R, Vanhille P, Vats A, Wang X, Warman B, Weleber RG, White SM, Wilson-Brackett C, Zand DJ, Eccles M, Schimmenti LA, Heidet L. Update of PAX2 mutations in renal coloboma syndrome and establishment of a locus-specific database. Hum Mutat. 2012 Mar;33(3):457-66. doi: 10.1002/humu.22020. Epub 2012 Jan 31. Citation on PubMed
  • Bower MA, Schimmenti LA, Eccles MR. PAX2-Related Disorder. 2007 Jun 8 [updated 2018 Feb 8]. In: Adam MP, Feldman J, Mirzaa GM, Pagon RA, Wallace SE, Bean LJH, Gripp KW, Amemiya A, editors. GeneReviews(R) [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2024. Available from Citation on PubMed
  • Capone VP, Morello W, Taroni F, Montini G. Genetics of Congenital Anomalies of the Kidney and Urinary Tract: The Current State of Play. Int J Mol Sci. 2017 Apr 11;18(4):796. doi: 10.3390/ijms18040796. Citation on PubMed or Free article on PubMed Central
  • Daniel L, Lechevallier E, Giorgi R, Sichez H, Zattara-Cannoni H, Figarella-Branger D, Coulange C. Pax-2 expression in adult renal tumors. Hum Pathol. 2001 Mar;32(3):282-7. doi: 10.1053/hupa.2001.22753. Citation on PubMed
  • Eccles MR, He S, Legge M, Kumar R, Fox J, Zhou C, French M, Tsai RW. PAX genes in development and disease: the role of PAX2 in urogenital tract development. Int J Dev Biol. 2002;46(4):535-44. Citation on PubMed
  • Galvez-Ruiz A, Lehner AJ, Galindo-Ferreiro A, Schatz P. Three New PAX2 Gene Mutations in Patients with Papillorenal Syndrome. Neuroophthalmology. 2017 May 8;41(5):271-278. doi: 10.1080/01658107.2017.1307995. eCollection 2017 Oct. Citation on PubMed or Free article on PubMed Central
  • Muratovska A, Zhou C, He S, Goodyer P, Eccles MR. Paired-Box genes are frequently expressed in cancer and often required for cancer cell survival. Oncogene. 2003 Sep 11;22(39):7989-97. doi: 10.1038/sj.onc.1206766. Citation on PubMed
  • Schimmenti LA, Manligas GS, Sieving PA. Optic nerve dysplasia and renal insufficiency in a family with a novel PAX2 mutation, Arg115X: further ophthalmologic delineation of the renal-coloboma syndrome. Ophthalmic Genet. 2003 Dec;24(4):191-202. doi: 10.1076/opge. Citation on PubMed
  • Sharma R, Sanchez-Ferras O, Bouchard M. Pax genes in renal development, disease and regeneration. Semin Cell Dev Biol. 2015 Aug;44:97-106. doi: 10.1016/j.semcdb.2015.09.016. Epub 2015 Sep 26. 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.