The genes responsible for differential segregation of the pre- and postmenopausal BC patients in the Indian cohort and the TCGA were dependent on differential expression of genes such as CNR2 (Luminal B), LRRC3B, EYA4, TMEFF2 (Luminal A), ESR2, GRIN2A, ERBB4, and NNAT (ER−ve aka Hmod and TNBC). This evidence concerns the gene ESR2 and breast cancer.