In contrast, TP53 mutations in AEL are characterized by a high-allelic frequency in leukemic cells (often with evidence of bi-allelic inactivation) and are also often identified in other cell populations than the leukemic cells (ie, T-cell compartment), supporting the idea that they arise at an early time point during disease development in an immature multipotent hematopoietic progenitor. This evidence concerns the gene TP53 and acute erythroid leukemia.