A total of seven studies comprising a total of 771 patients with pediatric ALL were included for the analysis of neutropenia; in comparison with the wild-type homozygote group, the ITPA 94C>A variant group was significantly associated with an increased risk of neutropenia (OR 2.38, 95% CI: 1.56–3.62; p = 0.005). This evidence concerns the gene ITPA and Decreased total neutrophil count.