BRCA2 Gene Analysis

What is BRCA2 gene analysis?

BRCA2 is a tumor suppressor gene involved in repairing DNA damage, especially double-strand breaks. When this gene carries a pathogenic variant, the cells' ability to repair DNA damage can decrease and the risk of developing certain cancers increases. BRCA2 variants are associated with breast and ovarian cancer in women and with breast and prostate cancer in men; the risk of pancreatic cancer may also increase in both sexes.

In BRCA2 gene analysis, all of the protein-coding regions of the gene are read in DNA extracted from blood, using methods such as next-generation sequencing. Complementary methods such as MLPA may be needed to detect deletions or duplications covering large sections of the gene; the scope of the test is stated in the laboratory report. Because variants can be inherited from either parent, the family history on the father's side is at least as important as that on the mother's side.

When is BRCA2 gene analysis ordered?

BRCA2 analysis is performed on a doctor's recommendation and with genetic counseling when a personal or family history of cancer suggests an inherited predisposition. In people diagnosed with cancer, the result can contribute to treatment and follow-up planning; in family members who have not been diagnosed, it helps them understand their personal risk.

• Breast cancer at a young age or cancer in both breasts
• Male breast cancer
• Ovarian, fallopian tube or peritoneal cancer
• A diagnosis of pancreatic cancer
• Prostate cancer that has spread or that occurs repeatedly in the family
• These cancers occurring in more than one family member
• A BRCA2 variant found in a family member

Where possible, testing a family member who has been diagnosed with cancer first can allow the results to be interpreted more meaningfully for other family members. BRCA2 is often examined together with BRCA1. If genetic testing has previously been done in your family, sharing the reports with your doctor makes it easier to determine which test is right for you.

How do you prepare for BRCA2 gene analysis?

No fasting is needed for this test, and the medications you take do not affect the result. Genetic counseling is recommended before the test; this consultation covers the scope of the test, the possible results and what the results could mean for you and your relatives. Noting down the cancer diagnoses on your mother's and father's sides, the ages at diagnosis and the degree of relationship in advance makes the assessment easier.

Genetic tests are performed with informed consent. If you have previously had a bone marrow or stem cell transplant, mention this; in that case a different type of sample may be needed, because the DNA obtained from blood may belong to the donor. Our nurse collects your blood sample at your home or workplace, and the sample is analyzed at an accredited laboratory.

How are BRCA2 gene analysis results interpreted?

The variants found are classified in the report as pathogenic, likely pathogenic, of uncertain significance, likely benign or benign. A pathogenic or likely pathogenic variant indicates an increased risk of developing the associated cancers; it does not mean that cancer will definitely develop. In this case, a monitoring program, risk-reducing options and recommending testing to family members are planned together with your doctor and through genetic counseling.

A variant of uncertain significance is not used on its own for treatment or surgical decisions and may be reclassified over time. Not finding a variant, on the other hand, does not mean that there is no cancer risk; the family history and risks associated with other genes are assessed separately. Your result should be interpreted by a medical geneticist or the doctor who follows your care, together with your personal and family history.