In 67 BCP‐ALL cell lines with the wild‐type NUDT15 genotype, the IC50 (day 7) value in six cell lines with NT5C2 and PRPS1 mutations was significantly higher than 61 cell lines without mutations (0.32 μM, p = 0.0011) (Figure 4E). The gene discussed is PRPS1; the disease is acute lymphoblastic leukemia.