Founder BRCA1/2 mutations in the Europe #1 July 8, 2010Posted by ramunas in BRCA, breast cancer, cancer genetics, genetic testing, ovarian cancer.
After a long silence, I’ll take my responsibility to provide readers with up to date information about founder BRCA1/2 mutations in the Europe from my review article which was just published in The EPMA Journal (International Reviews in Predictive, Preventive and Personalised Medicine, The Official Journal of the European Association for Predictive, Preventive and Personalised Medicine (PPPM) by Springer group.
The most significant and well characterized genetic risk factors for breast and/or ovarian cancer to date are germline mutations of the BRCA1 (MIM#113705; 17q chromosome; ) and BRCA2 (MIM#600185; 13q chromosome ) genes. In the general population, about 5–10% of all breast cancer and 10–15% of ovarian cancer cases can be attributed to these major genetic risk factors, which can explain around half of breast/ovarian cancer aggregation in some families [3, 4]. The prevalence of BRCA1/2 mutation carriers in the general population is around 0.2% (1/500) what accounts for BRCA1 mutation rate carriers of around 1/800 , however it can vary significantly among different countries or some ethnic groups due to founder effect .
The mutations in these high-penetrance genes confer a high life-time risk of breast and ovarian cancer. Women with an inherited BRCA1 mutation have a lifetime risk of 65–80% of developing breast cancer and 37–62% of developing ovarian cancer, while BRCA2 mutation carriers have a lifetime risk of 45–85% for breast cancer and 11–23% for ovarian cancer .
The identification of BRCA1 and BRCA2 mutation carriers and individualized risk assessment is an important procedure growing in clinical importance, since management protocols for mutation carriers become well established [8–10] and proven life-saving, risk-reducing preventive medical interventions exist [11–13]. Once mutation is identified in a given family, a very informative predictive (or presymptomatic) oncogenetic test can be offered virtually to all adult family members. Moreover, oncogenetic testing is becoming the powerful therapeutical predictive tool, as new targeted therapeutic opportunities, such as poly(ADP-ribose) (PARP) inhibitors [14, 15], emerge and chemosensitivity to platinum based therapy is constantly reported [16, 17].