RBL2 and chronic myelogenous leukemia, BCR-ABL1 positive: In the G1 (red) cell cycle phase, 7 cell cycle regulatory genes, including CDC20, CDKN2B, ATM, RBL2, RAD9A, CDK5RAP1, and CCNC, were significantly (p < 0.05) downregulated in CP CML compared with normal progenitors.