What does a negative BRCA1 or BRCA2 test result mean?
The answer depends on whether a family alteration is known. If a known alteration is not found, then the person does not have an increased risk for breast cancer and cannot pass it on to a child. If no BRCA1 or BRCA2 alteration has previously been found in the family, then a negative test result does not mean much. It’s impossible to tell if a person actually does have an alteration but the test missed it (false negative) or if a person truly does not have it (true negative). In addition, a person may have an alteration in a gene other than BRCA1 or BRCA2 that increases cancer risk but is not detected by this test. If the test finds an alteration that has never been seen before, then the risk of cancer for that person may be uncertain. Everyone has alterations in some of their genes that do not increase their risk of disease. In addition, breast cancer is a very common disease. In the majority of women diagnosed with breast cancer, it is not due to an inherited alteration. Therefore, w