PAX5 and infection: Although AID-deficient B-ALL exhibited a gene expression pattern similar to these human B-ALL28 (FDR = 0.005; FDR = 0.002) (Fig. 1d), the gene expression profiles between Pax5-het/Aid-KO B-ALL and Pax5-het/Aid-het B-ALL did not show any differences between them when we compared with gene expression profile derived from tumor cells from patients with B-ALL expressing or not AID27,28 (FDR = 0.290; FDR = 0.505) (Fig. 1e), indicating that the AID is not significantly contributing to the leukemic gene expression profile of infection-driven B-ALL.