Among the genes amplified in the focal regions were a cluster of HOX genes (HOXA7, HOXA9, HOXA10, HOXA11) on 7p15, AKT1 (14q32.33), IGF1R (15q26.3), ERBB2 and NEUROD2 (17q12), all of which have been reported in primary breast cancers (Table S1a, File S1). Here, HOXA9 is linked to breast cancer.