Gene editing of the chronic myeloid leukemia (CML) cell line K562 and primary CD34+ HSPCs with an AAV2/6 donor and Cas9 nuclease in the presence of NU7441 improved the frequency of HDR approximately two-fold, but some cellular toxicity was observed [90]. Here, CD34 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.