Four new cases of double heterozygosity for BRCA1 ... [Breast Cancer Res Treat. 2010] - PubMed result

"Double heterozygosity (DH) for BRCA1 and BRCA2 mutations is a very rare finding, particularly in non-Ashkenazi individuals, and only a few cases have been reported to date. In addition, little is known on the pathological features of the tumors that occur in DH cases and on their family history of cancer. Four carriers of pathogenic mutations in both BRCA1 and BRCA2 were identified among women who underwent genetic counseling for hereditary susceptibility to breast and ovarian carcinoma at three different Italian institutions"