Even though they had no family history that would make them eligible for genetic testing, about 1 in 40 postmenopausal women diagnosed with breast cancer before age 65 had a mutation linked to cancer in the BRCA1 or BRCA2 gene, a rate similar to Ashkenazi Jewish women, according to an analysis of data from the Women’s Health Initiative.
via BRCA Mutations More Common Than Thought in Older Women Diagnosed With Breast Cancer