In human ETV6-RUNX1 ALL, the ETV6-RUNX1 fusion gene is believed to initiate prenatally, yet the disease remains clinically latent until critical secondary events occur, leading to leukemic transformation – ‘pre-leukemia to leukemia’ (Mijušković et al., 2015; Bateman et al., 2010). Here, RUNX1 is linked to acute lymphoblastic leukemia.