RUNX1 and chronic myelogenous leukemia, BCR-ABL1 positive: In addition, cryptic and partial deletions of PRDM16 and RUNX1 without t(1;21)(p36;q22) and/or RUNX1-PRDM16 fusion were detected in a case of progressive CML suggesting that different mechanisms of chromosomal rearrangement may occur in these malignancies [225].