Independently, for the 38 breast cancer cell lines for which both expression and DNA copy number data were available [12] (and which were used in our DNA copy number analysis shown in Table 4) the correlation matrix for the ERBB2 CR and its neighboring genes was very similar (Additional file 4) to those produced for the breast cancer cohorts (Figures 6 and 7). The gene discussed is ERBB2; the disease is breast cancer.