1.   Doctors can perform tests to see if a woman carries the breast cancer gene.

2.   It seems likely that they achieve this by integration of the viral genes next to the cellular copy of a cancer gene.

3.   The drug blocks the action of the cancer gene.

4.   Already, Broach has found that a human cancer gene, called ras, is also in yeast cells and makes them lose control of their growth.

5.   Among them is Dr. Bert Vogelstein, a professor of oncology at Johns Hopkins School of Medicine, who discovered the colon cancer gene.

6.   And a test showed that her brother had inherited the colon cancer gene.

7.   And researchers now suspect that other breast cancer genes, two or more, will be found.

8.   As more is learned about the human genome, other breast cancer genes may show up.

9.   BRCA genes, short for breast cancer genes, fix DNA errors in cells.

10.   A host of cancer genes has been identified, as well, including hereditary forms of breast and colon cancer.