Family history of breast cancer does have influence on whether or not a woman is at risk for developing the disease. In fact, the risk of developing breast cancer is higher in women who have close relatives with the disease. For example, having a mother, sister, or daughter with the disease, referred to as a first-degree relative, doubles a woman’s chance of developing breast cancer. And, if a woman has two first-degree relatives such as a mother and sister with breast cancer, the risk increases by about three-fold.
Research also has revealed that certain inherited genes can increase the risk of developing breast cancer in some women. An inherited mutation of the BRCA1 and BRCA2 genes is the most common cause of familial breast cancer. In women with this mutation, the risk of developing breast cancer can be as high as 80 percent. While this particular gene mutation is most often found in Jewish women of Ashkenazi (Eastern Europe) origin, it can be found in women of any race or ethnicity.
Other inherited gene mutations such as ATM, p53, CHEK2, PTEN and CDH1 also can increase the risk of developing breast cancer. However, these gene mutations are more rare than the BRCA1 and BRCA2 genetic mutations.
While genetics does play a role, it is important to point out that less than 15 percent of all breast cancers occur in women with a family history with the disease. Since the majority of breast cancers develop in women without a family history, women more than 40 years of age should undergo a screening mammogram every year in order to detect breast cancer in the early stage of the disease.
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