the world. The actress candidly shared her courageous decision to undergo a preventative double-mastectomy, after testing showed she was at risk for the disease. Jolie writing in "the new york times,"... See More
the world. The actress candidly shared her courageous decision to undergo a preventative double-mastectomy, after testing showed she was at risk for the disease. Jolie writing in "the new york times," it is possible to find out through a blood test whether you are highly susceptible to breast and ovarian cancer. And then, take action. Since then, the angelina jolie effect has been in full force. The national society of genetic counselors reporting they have seen an uptick at treatment centers across the country. I think of it as the angelina gift, kicking up the conversation. Reporter: But the reality, only about 5% to 10% of women have a single rare gene that produces a high-risk of developing cancer. 90% of women who get breast cancer are more likely to have breast cancer because of lifestyle changes. What weight they are, how physically active they are. If they're drinking too much, smoking. Reporter:53-year-old ann's doctors believe she falls into the nongenetic pool. The physical therapist and once avid runner is currently in treatment for her second battle with breast cancer. Went in for a standard mammogram. A week before the holidays in 2007, and was totally shocked. Reporter: There is hope. Breastcancer.Org list a number of steps that can lower your breast cancer risks immediately. Including limiting your alcohol intake. Avoiding cook in plastics. A message angelina and her doctor hope millions of women would hear. And her doctor, dr. Kristi funk, who performed angelina jolie's surgery is here. And it is revolutionary what you are doing on the west coast. Great to spend time with you. We know that angelina has jump-started this conversation. But people still want to know more about genetic testing. Explain it to them. Genetic testing is easily done through a blood sample or just a scope. You can leave a genetic sampling and fresh breath. The question becomes difficult when you say who is appropriate for testing? That's where education needs to step up. That is. We asked that in an abc news poll. And 62% of women with a close relative diagnosed with the social secur disease are worried about their own health. The guidelines for genetic testing say look at mom and dad's side. First, second and third generation relatives. So, it goes quite far. What you're looking for is for one of those relatives to either have had breast cancer prior to age 50, or ovarian cancer at any age. Mom and dad. Dad can pass this gene down, too. Don't you have a quiz on your website to help people determine whether or not? I do. A link to the quiz is at brcagenemutation.Com. It gives you all of the information you need to know. And a five-question quiz takes 60 seconds and you can find out if testing is for you. We have a link on our website to your quiz and website. We were talking in my office. A fascinating conversation with you and your husband, andy. People who test positive and people who test negative. But there's a wide slot between. That's a huge number. That's so important. The number between. Of all americans, 1 million of us carry a mutation. But it will take 19 million high-risk people to find the 1 million. And those 18 million then that don't have braca were nigh enough to test. They don't just freefall back to normal population. We have to look at them and say, maybe you have another gene that we can best for. It's not just brca. Brca counts for 84%. Another 14%, we know about. We can test that. You may have that. If you don't have that, you still could have some form of elevated risk that warrants elevated screening. And you said to me, you're not here promoting surgery. You're promoting education. And so, everybody has to make that choice for themselves, as angelina did. Absolutely. She was at 13%. But she felt that, hey, with six children, and she wants to live life. That was too high for her. Is it a personal choice? It's absolutely personal. I love to sit down with my gene mutation carriers and figure out what is it about their life that answers? That's what we're trying to do today. Thank you for joining us. And give angelina all our best. What you're doing with pink lotus out there on the west coast, you're providing a spark. And information and hope. Thank you. And let's hope we can continue this relationship.
This transcript has been automatically generated and may not be 100% accurate.