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BAP1 tumor predisposition syndrome


BAP1 tumor predisposition syndrome is an inherited disorder that increases the risk of a variety of cancerous (malignant) and noncancerous (benign) tumors, most commonly certain types of tumors that occur in the skin, eyes, kidneys, and the tissue that lines the chest, abdomen, and the outer surface of the internal organs (the mesothelium). Affected individuals can develop one or more types of tumor, and affected members of the same family can have different types.

Some people with BAP1 tumor predisposition syndrome develop growths in the skin known as atypical Spitz tumors. People with this syndrome may have more than one of these tumors, and they can have dozens. Atypical Spitz tumors are generally considered benign, although it is unclear if they can become cancerous. Skin cancers are also associated with BAP1 tumor predisposition syndrome, including cutaneous melanoma and basal cell carcinoma.

A type of eye cancer called uveal melanoma is the most common cancerous tumor in BAP1 tumor predisposition syndrome. Although uveal melanoma does not usually cause any symptoms, some people with this type of cancer have blurred vision; small, moving dots (floaters) or flashes of light in their vision; headaches; or a visible dark spot on the eye.

People with BAP1 tumor predisposition syndrome are at risk of developing malignant mesothelioma, which is cancer of the mesothelium. When associated with BAP1 tumor predisposition syndrome, malignant mesothelioma most often occurs in the membrane that lines the abdomen and covers the abdominal organs (the peritoneum). It less commonly occurs in the outer covering of the lungs (the pleura).

A form of kidney cancer called clear cell renal cell carcinoma is also associated with the condition. Researchers are still determining whether other forms of cancer are linked to BAP1 tumor predisposition syndrome.

When they occur in people with BAP1 tumor predisposition syndrome, cancers tend to arise at a younger age and are often more aggressive than cancers in the general population. The cancerous tumors in BAP1 tumor predisposition syndrome tend to spread (metastasize) to other parts of the body. Survival of affected individuals with this syndrome is usually shorter than in other people who have one of these cancers. However, individuals with malignant mesothelioma as part of the BAP1 tumor predisposition syndrome appear to survive longer than those who have the cancer without the syndrome.


BAP1 tumor predisposition syndrome is a rare condition; its prevalence is unknown. More than 70 families with the condition have been described in the medical literature.


BAP1 tumor predisposition syndrome is caused by mutations in the BAP1 gene. The BAP1 protein acts as a tumor suppressor, which means it helps prevent cells from growing and dividing too rapidly or in an uncontrolled way. Its function is to remove molecules called ubiquitin from certain proteins (deubiquitination), which can affect the activity of the protein and its interactions with other proteins. By removing ubiquitin, BAP1 helps regulate diverse cellular processes. The BAP1 protein is thought to be involved in cell growth and division (proliferation), cell death, repair of damaged DNA, and control of gene activity.

Mutations in the BAP1 gene lead to production of an altered protein that cannot function normally and may be broken down prematurely. In addition to an inherited (germline) mutation in one copy of the gene, which is found in essentially every cell of the body, a second, non-inherited (somatic) mutation usually occurs in the normal copy of the gene in cells that give rise to tumors. Together, the germline and somatic mutations result in a complete loss of BAP1 protein function in tumor cells. A shortage of this protein's function likely impairs the removal of ubiquitin from certain proteins. Although it is unclear exactly how loss of BAP1 function leads 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.

Studies suggest that environmental and lifestyle factors help determine which types of tumor develop in individuals with BAP1 tumor predisposition syndrome. For example, exposure to asbestos likely contributes to the development of malignant mesothelioma. While asbestos increases the risk of malignant mesothelioma in the general population, the risk is even higher in individuals with a BAP1 gene mutation. It is not clear why certain tumor types are particularly associated with BAP1 tumor predisposition syndrome.


BAP1 tumor predisposition syndrome is inherited in an autosomal dominant pattern, which means one copy of the altered BAP1 gene increases the chance of developing one or more tumors. In most cases, an affected person has one parent with the condition.

People with a mutation in the BAP1 gene inherit an increased risk of tumor formation. Not all people with a gene mutation will develop a tumor.

Other Names for This Condition

  • BAP1-related tumor predisposition syndrome
  • COMMON syndrome
  • Cutaneous/ocular melanoma, atypical melanocytic proliferations, and other internal neoplasms

Additional Information & Resources

Genetic and Rare Diseases Information Center

Patient Support and Advocacy Resources

Clinical Trials

Catalog of Genes and Diseases from OMIM

Scientific Articles on PubMed


  • Baumann F, Flores E, Napolitano A, Kanodia S, Taioli E, Pass H, Yang H, Carbone M. Mesothelioma patients with germline BAP1 mutations have 7-fold improved long-term survival. Carcinogenesis. 2015 Jan;36(1):76-81. doi: 10.1093/carcin/bgu227. Epub 2014 Nov 7. Citation on PubMed or Free article on PubMed Central
  • Cheung M, Kadariya Y, Talarchek J, Pei J, Ohar JA, Kayaleh OR, Testa JR. Germline BAP1 mutation in a family with high incidence of multiple primary cancers and a potential gene-environment interaction. Cancer Lett. 2015 Dec 28;369(2):261-5. doi: 10.1016/j.canlet.2015.09.011. Epub 2015 Sep 26. Citation on PubMed or Free article on PubMed Central
  • Mochel MC, Piris A, Nose V, Hoang MP. Loss of BAP1 Expression in Basal Cell Carcinomas in Patients With Germline BAP1 Mutations. Am J Clin Pathol. 2015 Jun;143(6):901-4. doi: 10.1309/AJCPG8LFJC0DHDQT. Citation on PubMed
  • Ohar JA, Cheung M, Talarchek J, Howard SE, Howard TD, Hesdorffer M, Peng H, Rauscher FJ, Testa JR. Germline BAP1 Mutational Landscape of Asbestos-Exposed Malignant Mesothelioma Patients with Family History of Cancer. Cancer Res. 2016 Jan 15;76(2):206-15. doi: 10.1158/0008-5472.CAN-15-0295. Epub 2015 Dec 30. Erratum In: Cancer Res. 2017 Jun 1;77(11):3124. doi: 10.1158/0008-5472.CAN-17-0575. Cancer Res. 2018 Jan 1;78(1):309. doi: 10.1158/0008-5472.CAN-17-3445. Citation on PubMed or Free article on PubMed Central
  • Pilarski R, Carlo MI, Cebulla C, Abdel-Rahman M. BAP1 Tumor Predisposition Syndrome. 2016 Oct 13 [updated 2022 Mar 24]. 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
  • Popova T, Hebert L, Jacquemin V, Gad S, Caux-Moncoutier V, Dubois-d'Enghien C, Richaudeau B, Renaudin X, Sellers J, Nicolas A, Sastre-Garau X, Desjardins L, Gyapay G, Raynal V, Sinilnikova OM, Andrieu N, Manie E, de Pauw A, Gesta P, Bonadona V, Maugard CM, Penet C, Avril MF, Barillot E, Cabaret O, Delattre O, Richard S, Caron O, Benfodda M, Hu HH, Soufir N, Bressac-de Paillerets B, Stoppa-Lyonnet D, Stern MH. Germline BAP1 mutations predispose to renal cell carcinomas. Am J Hum Genet. 2013 Jun 6;92(6):974-80. doi: 10.1016/j.ajhg.2013.04.012. Epub 2013 May 16. Citation on PubMed or Free article on PubMed Central
  • Rai K, Pilarski R, Boru G, Rehman M, Saqr AH, Massengill JB, Singh A, Marino MJ, Davidorf FH, Cebulla CM, H Abdel-Rahman M. Germline BAP1 alterations in familial uveal melanoma. Genes Chromosomes Cancer. 2017 Feb;56(2):168-174. doi: 10.1002/gcc.22424. Epub 2016 Oct 26. Citation on PubMed
  • Rai K, Pilarski R, Cebulla CM, Abdel-Rahman MH. Comprehensive review of BAP1 tumor predisposition syndrome with report of two new cases. Clin Genet. 2016 Mar;89(3):285-94. doi: 10.1111/cge.12630. Epub 2015 Jul 14. Citation on PubMed or Free article on PubMed Central
  • Wiesner T, Obenauf AC, Murali R, Fried I, Griewank KG, Ulz P, Windpassinger C, Wackernagel W, Loy S, Wolf I, Viale A, Lash AE, Pirun M, Socci ND, Rutten A, Palmedo G, Abramson D, Offit K, Ott A, Becker JC, Cerroni L, Kutzner H, Bastian BC, Speicher MR. Germline mutations in BAP1 predispose to melanocytic tumors. Nat Genet. 2011 Aug 28;43(10):1018-21. doi: 10.1038/ng.910. Citation on PubMed or Free article on PubMed Central

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