For the TNBC subtype, although understanding of the identified subtype-specific genes is less than other two types, the roles of DGCR5 (Jiang et al., 2020), RAD51L1 (Stevens et al., 2011), and TTLL4 (Arnold et al., 2020) in breast cancer are well studied. The gene discussed is DGCR5; the disease is breast carcinoma.