Microarray studies have also shown that constitutional mutations in BRCA1 and BRCA2 influence the gene expression profile of malignant tissues.7–13 In primary tumors from breast epithelium, Hedenfalk et al. showed that there are different gene expression profiles in BRCA1 positive tumors, BRCA2 positive tumors and sporadic tumors.8 Comparison of gene expression patterns in ovarian cancers showed that BRCA1 and BRCA2 associated tumors differ significantly in their gene expression profiles.1, 2. The gene discussed is BRCA1; the disease is ovarian cancer.