Under a linear regression model a marked reduction in relative expression of TES (probe-set 202719_s_at) was observed in the common subtypes of precursor B ALL, including hyperdiploid, TEL-AML1, BCR-ABL, E2A-PBX1 (for each subgroup p < 0.001) and in T lineage ALL (p < 0.05) but not in MLL rearranged ALL (p = 0.20), when compared to CD34+ BM (Figure 3). Here, ABL1 is linked to acute lymphoblastic leukemia.