The above results suggested that the polymorphism of UGT1A1*28 gene was correlated with the incidence of neutropenia in cancer patients during IRI chemotherapy, and the incidence of wild-type (TA6/6) is higher in mild neutropenia, and the incidence of mutant type (TA6/7 + TA7/7) is higher in severe neutropenia. Here, UGT1A1 is linked to Decreased total neutrophil count.