Normal test results don't guarantee healthy genes. In some families, many women have had breast cancer, yet they all test normal for the known breast cancer mutations. These families may have an inherited form of breast cancer caused by an abnormality or other gene that simply hasn't been identified yet. Abnormal genes are just one of many risk factors for breast cancer. In fact, most cases of breast cancer do not involve an altered BRCA1 or BRCA2 gene. Statistics show that at most, 1 in 10 breast cancers cases involve an inherited altered gene. The bottom line is that the absence of BRCA1 or BRCA2 is by no means insurance against developing breast cancer. |
