Upon treating patients of ALL with l-asparaginase, a marked depletion in both extracellular and intracellular glutamine has been observed both in vitro (Bussolati et al. 1995; Uggeri et al. 1995) and in vivo (Ollenschläger et al. 1988; Reinert et al. 2006; Rudman et al. 1971). The gene discussed is ASPG; the disease is acute lymphoblastic leukemia.