We propose however that the increased incidence of the early T‐cell precursor‐ALL phenotype in adults explains the observed enrichment in ABD and mutations in ETV6, GATA3, RUNX1 and JAK3 in adult T‐ALL.11, 24, 29, 37, 41, 53, 54. This evidence concerns the gene RUNX1 and acute lymphoblastic leukemia.