Similarly, two studies comparing acquired copy number aberrations (CNAs) and copy neutral LOH in paired diagnosis and relapse samples in NPM1 mutant AML (Krönke et al., 2013) and unselected cases of AML (Parkin et al., 2013) found that reemergence or evolution of a founder or ancestral clone is typical in relapsed AML (Krönke et al., 2013). Here, NPM1 is linked to acute myeloid leukemia.