AP is a significant and potentially serious complication in pediatric patients with acute lymphoblastic leukemia (ALL) undergoing chemotherapy, particularly when asparaginase such as L-asparaginase (L-asp) or PEG-asparaginase (PEG-asp), a pegylated form of L-asp, is included in the treatment regimen (10–12). The gene discussed is ASPG; the disease is acute lymphoblastic leukemia.