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

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.

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.

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.