Transcript for How gene testing can prevent breast cancer at the earliest stages
And we're back with that new medical headline looking at how a vaccine could possibly prevent breast cancer using brca gene testing and linsey Davis has more on that. Reporter: Talking about this it's one of the most transformative health initiatives of our time. When people think about cancer research they think about finding cures but the goal of this nonprofit is prevention. Specifically for people with the brca gene. Take a look. Angelina Jolie shocked the world in 2013 when she had a preventive double mastectomy due to the brca gene giving carriers an increased Rick of getting breast cancer. Sisters Jan and Stacy took the same measure to save their lives. We knew it's in our family. Reporter: They too were brca positive and had double mastectomy six months apart. It was a really easy choice. It really was. Because, one, like we said we knew it was coming for us and needed to be there for our daughters. Reporter: The brca gene is hereditary resulting in an 86% chance of getting breast cancer and sisters lost a cousin to cancer and their mom, a two-time breast cancer survivor is now fighting ovarian cancer. They take turns caring for her. Then one day it hits me that my daughter might have to do this for me and it just is so frustrating and so -- gets you so angry. Reporter: Between the sisters they have three little girls under the age of 10 who all have a 50% chance of inheriting the gene. We don't want our daughters to have to go through that. Being a father, I want to do everything I can to stop that ever happening in them. Reporter: To that end they're putting their faith in a global research organization focused on preventing inherited cancers using the brca gene as the key. You guys are talking about prevention. This is prevention and you're not curing anything. You're avoiding having the disease ever. Reporter: Their plan is preliminary but holds potential. To have a vaccine available in the next ten years to prevent brya positive breast cancer from ever occurring? We know there are some cells going down the path of becoming cancerous early on and want to eliminate nature those from everyone who has a brca mutation. So that's vaccine, medications and these trials. Any of the trials. Reporter: Jan says she plans to have her daughters tested after they turn 18 and if they test positive she's hopeful by then a double mastectomy won't be their only option for prevention. There could be a vaccine for inherited cancers that kids get when they're around 12 or 13 years old and won't even have to think about any healthy cells turn nothing cancer cells. According to heritx, 10 to 20% have it. They say it has the characteristics that will work best against brca-related cancers and anticipate in two years they'll start clinical trials with people trying out this vaccine. The potential here is transformative and already identified the cells that are problematic. Now a matter of how to figure out how to eliminate them before they become cancerous. I have chills watching that story. Knowing the technology is just so in our favor so thank you so much for bringing us that. We appreciate it. Coming up next on "Gma" we
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