HLA-A and acute lymphoblastic leukemia: Four significantly (p-value <0.01) protective HLA-A alleles (A*33, A*01, A*03, and A*26) and six predisposing-alleles (A*24, A*31, A*23, A*30, A*68, and A*74) were found, with 50% of alleles as a whole either predisposing or protective in this high-risk ALL population (Figure 2A).