Screening for founder mutations in BRCA1 and BRCA2 in unselected Jewish women.

PURPOSE: There are two mutations in BRCA1 and one mutation in BRCA2 that are present in up to 2.5% of Ashkenazi Jewish women. Current guidelines for testing stipulate that a personal or family history of cancer be present to be eligible for testing. To date, population screening in this population has not been suggested. However, this may be rational. Little is known about the appropriateness of testing guidelines for the Jewish population or the level of interest in testing. METHODS: Eligible subjects were women who self-identified as Jewish, who were between the ages of 25 and 80 years, and who resided in Ontario. Subjects were recruited through an article in a national newspaper. Women were asked to complete a study questionnaire and a family history questionnaire and to provide a blood or saliva sample. The risk of carrying a BRCA mutation was estimated for each woman. Results A total of 2,080 women were enrolled onto the study. The overall mutation prevalence was 1.1% (0.5% for BRCA1 and 0.6% for BRCA2). Among the 22 mutation carriers, the mean estimate of carrying a BRCA mutation was 3.9%. Ten (45%) of the 22 women met the current Ontario Ministry of Health Guidelines criteria for testing. CONCLUSION: There is considerable interest for genetic testing among Jewish women at low risk of carrying a mutation. However, many women with mutations are ineligible for genetic testing under current guidelines. Approximately 1% of Jewish women carry a BRCA mutation, and these women should be considered to be candidates for genetic testing.

Influence of selected lifestyle factors on breast and ovarian cancer risk in BRCA1 mutation carriers from Poland.

It has been estimated that the lifetime risk of breast cancer among women who inherit a BRCA1 or BRCA2 mutation is as high as 80%, and the risk estimates for ovarian cancer range from 15 to 40%. Several environmental and lifestyle factors are believed to contribute to the development of breast cancer in the general population and it is of interest to establish if these factors operate among mutation carriers as well. To evaluate the effects of age of menarche, parity, breast-feeding, oophorectomy and oral contraceptive use, as well as smoking and coffee consumption, on the risks of breast and ovarian cancer, we conducted a matched case-control study of Polish women with BRCA1 mutations. There were 348 breast cancer patients, 150 ovarian cancer patients and similar numbers of age-matched controls. BRCA1 carriers with late age of menarche, lower parity and long-term breast-feeding were less likely to develop breast cancer. Oral contraceptives protected against ovarian cancer.