The main intrinsic subtypes of luminal, basal-like, and HER2+/ER− (Supplementary Figure 1) were identifiable in this Indian patient dataset, which is consistent with previous studies showing that the breast tumour intrinsic subtypes are conserved across ethnic groups (Yu et al, 2004; Carey et al, 2006). This evidence concerns the gene ERBB2 and breast neoplasm.