The terms BRCA1 and BRCA2 (sometimes pronounced "bracka" 1 and 2) generally refer to important portions of the human genome that make proteins in cells that suppress tumors (typically breast or ovarian cancer) by repairing DNA that may be damaged during the course of one's life. Any damage to the BRCA 1 or 2 gene segments therefore predisposes an individual to breast and ovarian cancer. Although there are many similarities between the two genes, there are many important differences that are important to understand. In general, both BRCA1 and BRCA2 mutations have been found to increase the lifetime risk of breast cancer very roughly between 50 and 85%. BRCA1 mutations however result in a higher risk of lifetime ovarian cancer (up to 60% in some studies) than BRCA2 (up to 20% in some studies). There is also a predilection for the two mutations to present with different types of cancer with some differences between the sexes. For example, BRCA2 is more likely to...
