A subtype of pediatric AML with an unfavorable prognosis is that characterized by the fusion gene CBFA2T3-GLIS2, caused by inv(16) (p13.3q24.3), which is present in 15–20% of pediatric non-Down syndrome acute megakaryoblastic leukemia (non-DS-AMKL) and about 7–8% of pediatric AML with normal karyotype [15,16], mostly found in infant patients (<3 years) [17,18]. The gene discussed is GLIS2; the disease is acute myeloid leukemia.