The first screening revealed that 28 SNPs were associated with the AUC (P < 0.05), and we analyzed the associations between the 28 SNPs and neutrophil counts in the other 32 patients, with the result that CYP39A1 (rs7761731) was found to be the only SNP significantly associated (P = 0.049 OR = 9.0) with the incidence of grade 4 neutropenia among 28 SNPs.