A notable example is the ABCB1 C3435T polymorphism, which has been associated with an elevated risk of doxorubicin induced neutropenia, likely due to its influence on glycoprotein expression and drug efflux capacity (Hao et al., 2020; Megías-Vericat et al., 2022). The gene discussed is ART4; the disease is Decreased total neutrophil count.