The fewest alterations were observed in Hmod (0.97% TSG and 1.3% ONC), followed by EPH (4.37% TSG and 4.9% ONC), EP (6.9% TSG and 2.7% ONC), and ER (2.7% TSG and 5% ONC), indicating differences in the alterations in oncogenes and tumor suppressors among breast cancer subtypes (Figure 2C). Here, ESR1 is linked to breast cancer.