The percentage of blasts in the samples studied was ≥ 20% except for four cases: two patients with newly diagnosed Down Syndrome (DS)-related AML (5% and 13% blasts, respectively), one patient was initially diagnosed with AML with myelodysplasia-related changes of whom only a post-treatment sample with 9% blasts was available for testing, and one patient with relapsed AML with NPM1 mutation (15% blasts). This evidence concerns the gene NPM1 and Down syndrome.