Our hypothesis was that matched tumor sequencing could be helpful in pinpointing genetic bases of suspected predisposition to BC in patients without pathogenic mutations in BRCA1, BRCA2, TP53, and CHEK2. In 735 cancer-related genes, we identified a mean of 4.7 variants per patient, with some in silico features of pathogenicity. Here, BRCA1 is linked to neoplasm.