Professor of medicine Gil Welch surprised by huge response to Angelina Jolie 's op - ed . The few women who are likely to have the mutation are also likely to know they may have it based on the oldest genetic test of all : a strong family history of cancer . Welch thinks women might wonder if they , too , should have preventive mastectomies . Welch : But 99 % of women do not have the BRCA1 mutation that raises the risk of breast cancer . He believes women should look at family history before getting tested for the mutation .
Professor of medicine Gil Welch surprised by huge response to Angelina Jolie 's op - ed . Welch thinks women might wonder if they , too , should have preventive mastectomies . Welch : But 99 % of women do not have the BRCA1 mutation that raises the risk of breast cancer . He believes women should look at family history before getting tested for the mutation .