Differences in the CNAs of several focal peaks were found: HER2-low tumors showed significantly higher levels of 17q12 gain/amplification (28.5% vs. 5.2%, false discovery rate (FDR) <0.001, mainly attributed to gains) and lower levels of 17q11.2 loss/deletion (21.3% vs. 51.7%, FDR <0.001) and 17q21.31 loss/deletion (22.3% vs. 51.7%, FDR <0.001) than HER2-0 tumors (Fig. 5a), which was also validated in the TCGA-BRCA (The Cancer Genome Atlas Breast Invasive Carcinoma) cohort (Supplementary Fig. S10e–g). Here, ERBB2 is linked to invasive breast carcinoma.