BRCA-1 and BRCA-2

Norm
This mutation is detected in approximately 1 in 300 women

Synonyms: breast cancer 1 gene and breast cancer 2 gene, Breast cancer susceptibility genes
Blood
Tube blue or yellow (citrate or ACD)

If women have mutations in these genes, the likelihood of developing breast cancer is 60% higher than in other women, as well as a higher risk of ovarian cancer by 15-40%. With this mutation, cancer can occur in women at a younger age than usual, i.e., even before menopause. Blood is tested and tissue biopsy is not necessary.

The clinical significance of the study is low. A negative test result does not mean that a woman will not develop these forms of cancer. About 90-95% of women with breast cancer do not have expressed BRCA genes. In addition, in the U.S. population, the average lifetime risk of breast cancer is estimated at 12%, and ovarian cancer at 1.4%. The risk increases significantly with age. On the other hand, having BRCA genes does not necessarily mean that a woman will develop these forms of cancer. According to U.S. laboratory data, this test is most often prescribed at the request of the patients themselves. Women with identified BRCA mutations are recommended to undergo mammograms, transvaginal sonography, and laboratory tests: CA 125 and CA 15-3 more frequently. Only 0.2% of women in the U.S. are carriers of BRCA genes. Similar studies have not yet been conducted in Lithuania. Men with identified BRCA-1 have almost no increased risk of breast cancer, while men with BRCA-2 are more likely to develop cancer than representatives of the control population. If men are found to have any of these mutations, the likelihood of developing prostate cancer is slightly higher (16% higher than the control population).

Source | Handbook of Basic Laboratory Tests | Doctor of Medical Sciences Gintaras Zaleskis