A new study designed to investigate the appropriateness of current BRCA1 and BRCA2 mutation testing guidelines for Ashkenazi Jewish women has challenged current Canadian testing guidelines. Two relevant mutations in BRCA1 and one mutation in BRCA2 are present in up to 2.5% of Ashkenazi Jewish women. Current Canadian guidelines for testing require a personal or family history of cancer for a Jewish woman to be eligible for testing. (Similar guidelines are used by Medicare and health insurance companies in the U.S., although note that the requirements to be eligible for testing can be even more stringent for non-Jewish women). Up until now, population screening in this group has not been suggested. The study included 2,080 women between the ages of 25 and 80 who resided in Ontario and who self-identified as Jewish. Participants were recruited by means of an article in a national newspaper. Most of them had no family history of breast cancer. The risk of being a BRCA mutation carrier was estimated for each participant before testing, based on data collected through questionnaires. The overall mutation incidence was found to be 1.1% (0.5% BRCA1 and 0.6% BRCA2) among the study participants. Among the 22 confirmed mutation carriers, the mean estimate of carrying a BRCA mutation was 3.9%. Only 10 of the 22 women met the criteria for testing. Apparently, many Jewish women who actually do have mutations are ineligible for genetic testing under current guidelines. The authors conclude that Ashkenazi Jewish women should be considered to be candidates for genetic testing.

BRCA testing can influence behavior and save lives

Women with BRCA1 or BRCA2 breast cancer gene mutations have a lifetime risk of breast cancer of approximately 70% and 50%, respectively. The lifetime ovarian cancer risks for carriers are approximately 35% and 20%, respectively. Unlike some other diseases influenced by genetic makeup for which there are no available preventative measures or treatments, women who test positive for BRCA1 or BRCA2 mutations can take a number of steps to reduce their risks of breast and ovarian cancer. In addition, awareness of such a mutation may influence important family planning decisions. Women with BRCA1 mutations are more likely to be infertile due to primary ovarian insufficiency. On the other hand, an early first pregnancy does not confer protection against breast cancer for BRCA1 or BRCA2 mutation carriers as it appears to do for non-carriers.

Knowledge of a BRCA1 or BRCA2 mutation in one family member may cause other family members (including men) to be tested or at least be more vigilant in performing breast self-exams, obtaining regular screening for breast cancer, and paying attention to possible symptoms of ovarian cancer. Furthermore, women and men with known BRCA1 or BRCA2 mutations can take steps, starting with pregnancy and infancy, to protect their daughters and sons from breast cancer.