In addition, we compared the frequency of the most common amplifications to those in breast cancer cases diagnosed before 45 years of age in The Cancer Genome Atlas (TCGA) Research Network (http://cancergenome.nih.gov/) [20] as well as in three published studies with accessible age and array-CGH data [21–23], and we found that the frequency of most amplifications, in particular, regions containing HER2 and possibly CCND1, still appeared higher compared to breast cancer in the general population (Table B in S1 File). Here, ERBB2 is linked to breast cancer.