This page was reviewed under our medical and editorial policy by
Eric Fowler, MS, LCGC, Manager, Clinical Genetics, Western Region & Licensed Certified Genetic Counselor
This page was reviewed on November 15, 2021.
BAP1 tumor predisposition syndrome, also known as BAP1-TPDS or COMMON syndrome, is an inherited genetic disorder that may increase the risk of certain types of tumors, both cancerous and noncancerous.
The BAP1 gene is involved in protein coding, which is important for transcribing genes in your body from DNA into mRNA. BAP1-TPDS is a rare disorder—so much is still unknown about its prevalence. So far, researchers have identified it in more than 70 families, according to the U.S. National Library of Medicine.
If your doctor is concerned about BAP1-TPDS, this guide may help you learn more about this condition.
Having BAP1-TPDS may increase your risk of developing certain kinds of cancer. This is because the BAP1 gene suppresses tumors in your body by preventing cells from dividing too rapidly and repairing acquired DNA damage. When mutations occur in the BAP1 gene, the regulating ability is lost, and tumors can occur more frequently.
Patients with BAP1-TPDS may develop tumors in the following areas.
There may be more cancer and tumor types linked to BAP1-TPDS that are yet to be discovered.
Because cancers linked to BAP1-TPDS are rare, researchers are still learning about their overall survival rates. So far, research suggests that people with BAP1-TPDS tend to develop cancers at a younger age, with the cancer more likely to spread elsewhere. However, patients with mesothelioma and BAP1-TPDS may have higher survival rates than those without BAP1-TPDS.
Because BAP1-TPDS is an inherited condition, your risk increases if a family member also has it. Usually, people with BAP1-TPDS have a parent with the syndrome.
It’s also important to remember that being diagnosed with BAP1-TPDS doesn’t necessarily mean you’ll develop tumors. Some research shows that, for patients with BAP1-TPDS, environmental factors may increase the risk of developing tumors, such as exposure to asbestos in the case of malignant mesothelioma.
Because BAP1-TPDS is hereditary and may be silent for a while, you may not experience symptoms or feel any differently.
However, uveal melanoma, which is the most common cancer associated with BAP1-TPDS, may cause the following symptoms:
Other cancers associated with BAP1-TPDS include cutaneous melanoma, mesothelioma and clear cell renal cell carcinoma.
Cutaneous melanoma symptoms may include:
Mesothelioma associated with BAP1-TPDS most often grows in the abdominal lining (peritoneum) but also sometimes in the membranes around the lungs. It may cause the following symptoms:
Clear cell renal cell carcinoma symptoms may include:
If you experience any of the symptoms above, or if you have concerns about a genetic predisposition to cancer, it’s always a good idea to speak with your doctor. Some cancers are known to have a genetic link, even if you don’t have BAP1-TPDS, so always seek medical advice if you have any questions or concerns.
Genetic testing is the only way to diagnose BAP1-TPDS. During genetic testing, a tissue sample is taken, often from blood, skin or hair. The tissue is examined by a pathologist, who studies the chromosomes and DNA for signs of a genetic disorder like BAP1-TPDS.
Before consenting to genetic testing, talk to your doctor or genetic counselor about the benefits of and considerations for genetic testing so that you’re fully informed. If your doctor has recommended genetic testing, many health insurers cover the cost.
If you’re diagnosed with BAP1-TPDS, your doctor may provide you with more details about what this means for your health. It can be an overwhelming and confusing time, so ask plenty of questions to help better understand what BAP1-TPDS means for you.
If you’ve been diagnosed with BAP1-TPDS, your doctor may refer you to an expert who specializes in genetic disorders or rare tumors. Patients with BAP1-TPDS may need more frequent diagnostic tests since there’s an increased risk of developing a tumor.
If a benign or cancerous tumor occurs, your medical team can explain the appropriate course of treatment depending on its type, size and severity.
Some patients with BAP1-TPDS also choose to participate in clinical trials, which may be a way to try new treatments and help to advance research for the benefit of others with the syndrome.