Prior work suggests that the ETV6::RUNX1 fusion is the first hit of a “two-hit” leukemia, with a second lesion (such as loss of ETV6 or gain of RUNX1, among others) acting as the driver of the leukemia (Kaczmarska et al., 2023; Rodríguez-Hernández et al., 2021). Here, RUNX1 is linked to leukemia.