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BAP1 gene

BRCA1 associated protein 1

Normal Function

The BAP1 gene provides instructions for making a protein called ubiquitin carboxyl-terminal hydrolase BAP1 (shortened to BAP1). This protein functions as a deubiquitinase, which means it removes a molecule called ubiquitin from certain proteins. The presence of ubiquitin molecules on a protein can affect the activity of the protein and its interactions with other proteins. The ubiquitin "tag" also promotes breakdown (degradation) of a protein. By removing ubiquitin, BAP1 helps regulate the function of many proteins involved in diverse cellular processes. The BAP1 protein is thought to help control cell growth and division (proliferation) and cell death. Studies suggest that it is involved in the progression of cells through the step-by-step process they take to replicate themselves (called the cell cycle) and that it plays roles in repairing damaged DNA and controlling the activity of genes.

Although the exact mechanism is unclear, the BAP1 protein acts as a tumor suppressor. Tumor suppressor proteins help prevent cells from growing and dividing too rapidly or in an uncontrolled way.

Health Conditions Related to Genetic Changes

BAP1 tumor predisposition syndrome

Mutations in the BAP1 gene cause BAP1 tumor predisposition syndrome. People with this condition have an increased risk of developing many types of noncancerous (benign) and cancerous (malignant) tumors, particularly certain tumors of the skin (atypical Spitz tumors, cutaneous melanoma, and basal cell carcinoma); eyes (uveal melanoma); kidneys (clear cell renal cell carcinoma); and a tissue called the mesothelium that lines the chest, abdomen, and internal organs (malignant mesothelioma). Researchers are still determining whether other forms of cancer are linked to BAP1 tumor predisposition syndrome.

Affected individuals inherit a mutation in one copy of the BAP1 gene. These mutations, which are present in essentially every cell of the body, are classified as germline mutations. Most germline BAP1 gene mutations lead to an abnormally short BAP1 protein that is likely broken down prematurely. Other germline mutations change single protein building blocks (amino acids) in the BAP1 protein and likely impair its function. In most cases, a second, non-inherited (somatic) mutation occurs in the normal copy of the gene in cells that give rise to tumors. Together, the germline and somatic mutations lead to a loss of BAP1 protein function in tumor cells.

Reduction or loss of this protein's function likely prevents the removal of ubiquitin molecules from certain proteins. Although it is unclear exactly how changes in BAP1 function lead to BAP1 tumor predisposition syndrome, researchers speculate that altered activity of proteins normally regulated by BAP1 deubiquitination may promote cell proliferation or survival, resulting in tumor formation.

More About This Health Condition


MedlinePlus Genetics provides information about Cholangiocarcinoma

More About This Health Condition


MedlinePlus Genetics provides information about Melanoma

More About This Health Condition

Other cancers

Somatic BAP1 gene mutations have been found in uveal melanoma, malignant mesothelioma, and clear cell renal cell carcinoma tumors in the absence of a germline BAP1 gene mutation. In these cases, the cancers occur in people with no family history of the cancer and are considered sporadic. Affected individuals do not develop additional tumor types associated with BAP1 tumor predisposition syndrome (described above).

Other Names for This Gene

  • BRCA1 associated protein-1 (ubiquitin carboxy-terminal hydrolase)
  • cerebral protein 6
  • cerebral protein-13
  • HUCEP-13
  • hucep-6
  • KIAA0272
  • ubiquitin carboxyl-terminal hydrolase BAP1
  • UCHL2

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


  • Alakus H, Yost SE, Woo B, French R, Lin GY, Jepsen K, Frazer KA, Lowy AM, Harismendy O. BAP1 mutation is a frequent somatic event in peritoneal malignant mesothelioma. J Transl Med. 2015 Apr 16;13:122. doi: 10.1186/s12967-015-0485-1. Citation on PubMed or Free article on PubMed Central
  • Daou S, Hammond-Martel I, Mashtalir N, Barbour H, Gagnon J, Iannantuono NV, Nkwe NS, Motorina A, Pak H, Yu H, Wurtele H, Milot E, Mallette FA, Carbone M, Affar el B. The BAP1/ASXL2 Histone H2A Deubiquitinase Complex Regulates Cell Proliferation and Is Disrupted in Cancer. J Biol Chem. 2015 Nov 27;290(48):28643-63. doi: 10.1074/jbc.M115.661553. Epub 2015 Sep 28. Citation on PubMed or Free article on PubMed Central
  • Eletr ZM, Wilkinson KD. An emerging model for BAP1's role in regulating cell cycle progression. Cell Biochem Biophys. 2011 Jun;60(1-2):3-11. doi: 10.1007/s12013-011-9184-6. Citation on PubMed or Free article on PubMed Central
  • Jensen DE, Proctor M, Marquis ST, Gardner HP, Ha SI, Chodosh LA, Ishov AM, Tommerup N, Vissing H, Sekido Y, Minna J, Borodovsky A, Schultz DC, Wilkinson KD, Maul GG, Barlev N, Berger SL, Prendergast GC, Rauscher FJ 3rd. BAP1: a novel ubiquitin hydrolase which binds to the BRCA1 RING finger and enhances BRCA1-mediated cell growth suppression. Oncogene. 1998 Mar 5;16(9):1097-112. doi: 10.1038/sj.onc.1201861. Citation on PubMed
  • Kumar R, Taylor M, Miao B, Ji Z, Njauw JC, Jonsson G, Frederick DT, Tsao H. BAP1 has a survival role in cutaneous melanoma. J Invest Dermatol. 2015 Apr;135(4):1089-1097. doi: 10.1038/jid.2014.528. Epub 2014 Dec 18. Citation on PubMed or Free article on PubMed Central
  • Matatall KA, Agapova OA, Onken MD, Worley LA, Bowcock AM, Harbour JW. BAP1 deficiency causes loss of melanocytic cell identity in uveal melanoma. BMC Cancer. 2013 Aug 5;13:371. doi: 10.1186/1471-2407-13-371. Citation on PubMed or Free article on PubMed Central
  • Pena-Llopis S, Vega-Rubin-de-Celis S, Liao A, Leng N, Pavia-Jimenez A, Wang S, Yamasaki T, Zhrebker L, Sivanand S, Spence P, Kinch L, Hambuch T, Jain S, Lotan Y, Margulis V, Sagalowsky AI, Summerour PB, Kabbani W, Wong SW, Grishin N, Laurent M, Xie XJ, Haudenschild CD, Ross MT, Bentley DR, Kapur P, Brugarolas J. BAP1 loss defines a new class of renal cell carcinoma. Nat Genet. 2012 Jun 10;44(7):751-9. doi: 10.1038/ng.2323. Erratum In: Nat Genet. 2012 Sep;44(9):1072. Citation on PubMed or Free article on PubMed Central
  • Royer-Bertrand B, Torsello M, Rimoldi D, El Zaoui I, Cisarova K, Pescini-Gobert R, Raynaud F, Zografos L, Schalenbourg A, Speiser D, Nicolas M, Vallat L, Klein R, Leyvraz S, Ciriello G, Riggi N, Moulin AP, Rivolta C. Comprehensive Genetic Landscape of Uveal Melanoma by Whole-Genome Sequencing. Am J Hum Genet. 2016 Nov 3;99(5):1190-1198. doi: 10.1016/j.ajhg.2016.09.008. Epub 2016 Oct 13. Citation on PubMed or Free article on PubMed Central
  • Ventii KH, Devi NS, Friedrich KL, Chernova TA, Tighiouart M, Van Meir EG, Wilkinson KD. BRCA1-associated protein-1 is a tumor suppressor that requires deubiquitinating activity and nuclear localization. Cancer Res. 2008 Sep 1;68(17):6953-62. doi: 10.1158/0008-5472.CAN-08-0365. Citation on PubMed or Free article on PubMed Central
  • Yu H, Pak H, Hammond-Martel I, Ghram M, Rodrigue A, Daou S, Barbour H, Corbeil L, Hebert J, Drobetsky E, Masson JY, Di Noia JM, Affar el B. Tumor suppressor and deubiquitinase BAP1 promotes DNA double-strand break repair. Proc Natl Acad Sci U S A. 2014 Jan 7;111(1):285-90. doi: 10.1073/pnas.1309085110. Epub 2013 Dec 17. Citation on PubMed or Free article on PubMed Central

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