Internal tandem duplication (ITD) mutations of the FLT3 gene occurred in nearly 24% of adult AML patients [3]; the other common mutant type of FLT3 which occurred in the activation loop of the tyrosine kinase domain (TKD), mainly at aspartic acid 835, was found in approximately 7% of AML patients [4]. The gene discussed is FLT3; the disease is acute myeloid leukemia.