Hadassah Medical Center researchers have detected two “founder” BRCA1/2 genetic mutations in Sephardic Jews who are descendants of Jews who were expelled from Spain in 1492.

The discovery emerged through analyzing DNA samples from patients of Sephardic origin who have breast cancer and/or ovarian cancer along with a family history of these cancers. The frequency of the two mutations was 26–31% among Sephardic high-risk families, in contrast to 3% among the full cohort of 177 patients of this origin who were tested by Hadassah.

As a result of these findings, Dr. Michal Sagi of Hadassah’s Department of Genetics and Metabolic Diseases and her study collaborator, Dr. Israela Lerer, head of the Molecular Laboratory, recommend testing for the two mutations in women of Sephardic origin who apply for BRCA testing as a result of personal and/or family history of breast or ovarian cancer. They also suggest adding these mutations to the five mutations included in “The Jewish Panel” of BRCA1/2 mutations being tested for in Israel.

The researchers’ findings are reported in the November 2010 issue of Familial Cancer. Dr. Sagi also recently gave a presentation to general physicians in Israel to advise them about referring Sephardic patients for testing. Because of a widely held assumption that Ashkenazi women are those with the genetic tendency for BRCA1/2 genetic mutations, physicians might typically assume that patients of Sephardic background are not at risk. The newest research, she reports, shows that they can no longer assume this.