The incidence of detectable pre-leukemia in asymptomatic children is many times that of the incidence of overt childhood BCP-ALL; for example, ETV6::RUNX1+ pre-leukemia is approximately 100-500x more common than ETV6::RUNX1+ BCP-ALL (37, 38). This evidence concerns the gene RUNX1 and acute lymphoblastic leukemia.