Zora: I am a 20-year survivor of breast cancer and just showing other women that you can survive this disease gives them hope, a lot of hope.

Announcer: Breast cancer has been a part of Zora's family tree for at least four generations. Her mother, grandmother, great-grandmother, three great aunts, three sisters, and a niece have all had the disease. In 1984, Zora and other family members took part in a National Cancer Institute study that led to the identification, in 1994, of the first breast cancer gene mutation, called breast cancer I, or BRCA I. The gene, often associated with people of Ashkenazi Jewish descent, causes a greatly increased risk of breast cancer. Zora and her relatives who carry the gene also have an increased risk of ovarian cancer.

Interviewer: When there was a specific gene identified for breast cancer, what was the reaction of your family?

Zora: My family was very grateful, because I think my mom was probably my leading advocate for breast cancer, because she always told us that she knew that she called it our hereditary -- our pre-disposition for breast cancer, so she always knew there was probably something going on within our family that caused us to have breast cancer, so all of the terminology that we use today certainly was not used then, but it was the same thing. We knew that there was probably something, a gene of some kind, that caused every single woman in my family, never skipping a generation, to be diagnosed with breast cancer.

Announcer: And it was her family's awareness of the disease that taught Zora valuable lessons about early detection and early treatment.

Zora: My mother used to always say to us, if we used common sense, science would catch up with us. I was first diagnosed with breast cancer at age 31. I found a small lump in my breast during a routine breast self-examination and I knew exactly what to do. We had a biopsy done and I was diagnosed with breast cancer and I immediately went into surgery and had a mastectomy, and I had a good life, so I wanted to live and I just had an attitude that I was going to overcome this diagnosis of breast cancer.

Announcer: Zora has a personal mission to educate her own family. A new generation of women has reached adulthood. She has 22 nieces and they are all at risk for inheriting the BRCA I gene. In Dallas, Texas, she organized a retreat, bringing her nieces together to discuss their options.

Zora: My nieces are very well-educated, they know to never miss a doctor's appointment, so I don't worry about them and their health so much. I do worry that they are at risk and I wish they weren't.

Announcer: For women who have the BRCA I gene, the most radical option is a prophylactic mastectomy, where healthy breasts are removed. This is effective in preventing breast cancer in about 90 percent of cases.

Zora: I think prophylactic mastectomy is a choice, it is an option for women who believe that having prophylactic mastectomy may prevent them from having breast cancer. I have a niece who's had prophylactic mastectomy.

Announcer: Another preventative option for high-risk women is to take tamoxifen, a drug long used to treat cancer.

Dr. Dewitty: In Zora Brown's case, for example, if we had tamoxifen out -- would that have helped? She sure would have been on it. So we know that tamoxifen, in a certain number of women, will not only treat it effectively, but prevent breast cancer.

Zora: I do everything that I think I can possibly do to detect anything that may possibly go wrong with me. I am very, very proactive. I don't like for anything to be uncomfortable, so the least little problem I have, I am at somebody's door, knocking on it, saying, "Fix this," because I don't want hurt. I don't want to die -- I intend to live a long time. And so I am one of those people that believes that if there are things available to you, that you can use to prolong your life, use them.