The results showed that the incidence of grade 0–2 and grade 3–4 neutropenia in the course of IRI chemotherapy was significantly different from that of UGT1A1*28 wild-type (TA6/6) compared with mutant type (TA6/7 + TA7/7), respectively [RR = 1.21, 95%CI (1.09, 1.36), P = 0.0007] and [RR = 0.51, 95%CI (0.40, 0.67), P < 0.00001], respectively, as shown in Figure 10. This evidence concerns the gene UGT1A1 and Decreased total neutrophil count.