TP53, the tumor suppressor (Baker et al., 1989; Rivlin et al., 2011), PIK3CA kinase (Karakas et al., 2006), and the epidermal growth factor receptor ErbB-2 and EGFR (Tebbutt et al., 2013), reported in multiple subtypes of cancer, are localized at the bottom right corner of the gene-variant map, suggesting the contribution of these genes to cancer in general with lower specificity to breast cancer compared to BRCA1 and BRCA2 (Figure 1). This evidence concerns the gene ERBB2 and breast cancer.