ERG expression in AML influences EFS of MLL-rearranged patients. (A) ERG expression in AML subgroups. ERG expression relative to ABL housekeeping gene was measured by real-quantitative PCR. RQ is the relative quantity of ERG expression with respect to the average of its expression in healthy bone marrows (N = 17) calculated by comparative ΔΔCt method. CBF indicates core binding factor rearrangements; and CN, cytogenetically normal. (B) Probability of event-free survival in children with MLL-rearranged AML according to ERG expression. Event-free survival (EFS) for patients MLL-rearranged with high (73.3%) vs low (18.3%) ERG expression.