One subgroup, comprising 16% of B-other cases (4% of the entire BCP ALL cohort), harboured rearrangements of the double homeobox 4 (DUX4) gene and overlapped with a previously described group of patients with a homogenous gene-expression profile and frequent ERG deletions6, 14, 15. This evidence concerns the gene DUX4 and acute lymphoblastic leukemia.