The genetics of breast cancer. At first, it was hoped that there would be only one or a few alleles of this gene, and that testing for the bad alleles would allow women and their physicians to take preventative steps.
Current indications are that other genes are also involved.
We are going to talk about the patterns of inheritance that led researchers to suspect a genetic tendancy to breast cancer, and about how a bad allele could cause cancer to develop. When these cells are turned on again, they begin to divide rapidly, forming a tumor. Not all tumors are cancer and not all cancers grow equally rapidly. In the worst cases, not only do these cells divide rapidly, but they begin to migrate to other parts of the body where they settle and again begin to divide rapidly. In breast cells, proliferation is stimulated by the hormones circulating during pregnancy and lactation.