PPM1D, protein phosphatase Mn2+/Mg2+-dependent 1D, is a DNA damage response regulator that is frequently mutated in clonal hematopoiesis and is present in about 20% of patients with therapy-related AML or MDS; PPM1D mutations confer a survival advantage onto hematopoietic clones by rendering them resistant to DNA-damaging agents, such as cisplatin [13]. Here, PPM1D is linked to acute myeloid leukemia.