,27 NPM1 is also one of the most common genetic mutations in AML and about 30% of AML patients with mutations in the 12th exon of NPM1, which leads to a frameshift mutation at the C-terminus, producing an additional leucine and valine-rich nuclear export signal (NES) and resulting in the cytoplasmic localization of mutant NPM1 protein, NPMc+.28 The gene discussed is NPM1; the disease is acute myeloid leukemia.