Possible New Gene Markers for Cancer Risk
Posted on May 02 2013
Scientists recently reported that a huge international effort, involving more than 100 institutions and genetic tests on 200,000 people, has uncovered dozens of signposts in DNA that help reveal a person’s risk for breast, ovarian and prostate cancer. This mega-collaboration is the latest to learn more about the intricate mechanisms that lead to cancer. The headway seems significant in many ways and has potential payoff for ordinary people. Someday there may be genetic tests that help identify women with the most to gain from mammograms and men who could benefit most from PSA tests and prostate biopsies. This could also lead to possible genetic clues that might lead to new treatments in the future.
One analysis suggests that men whose family history gives them about a 20% risk for prostate cancer could be the same genetic marker that can identify those whose real risk is 60%. The markers could also make a difference for women with BRCA gene mutations. These mutations put them at high risk for breast cancer, but researchers may be able to separate those whose lifetime risk exceeds 80% from women whose risk is about 20-50%. One doctor said this might mean that some women would choose to monitor for cancer rather than having healthy breasts removed.
Breast cancer is the most common malignancy among women in the world, with more than one million new cases popping up each year. Prostate cancer is the second most common cancer among men after lung cancer, about 900,000 new cases every year. Ovarian cancer accounts for 4% of all cancers diagnosed in women causing about 225,000 cases worldwide. Scientists have found 49 new risk markers for breast cancer and a few others that modify breast cancer risk from rare mutated genes, 26 for prostate cancer and 8 for ovarian cancer. Each marker, individually, has only a slight impact on the risk estimation and are too small to be useful on their own, but combined and added to previously known markers would help to reveal a person’s risk.
Genetic testing could be useful in identifying people who should get mammograms or PSA testing. Scientists say that gene testing using all known markers could reduce the number of mammograms and PSA tests by around 20% with only a small cost in cancer cases missed.
This is an extensive, on-going study that shows promise of being a huge help to cancer prevention in the future. Maybe someday the average lifespan for a human will be 150, as long as they come up with some eternal youth drugs between now and then! For more information on this study go to abcnews.go.com.