ERBB2 and breast neoplasm: Rey-Vargas et al. reported a higher proportion of Native American ancestry in Colombian patients with ER+ /HER2+ (45%) than in ER + /HER2− (40%) breast tumours, and Marker et al. demonstrated a higher risk of HER2 + BC with increasing proportions of Native American ancestry in Colombian, Mexican and Peruvian women [34, 35].