For unbiased confirmation of the effect of CDADC1 in comparison with known cellular determinants of dC-analog resistance, we performed a genome-wide CRISPR/Cas9 KO chemogenomic screen in the pre-B acute lymphocytic leukemia NALM-6 cell line, grown in the presence of gemcitabine at a dosage that partially inhibited cell growth to identify genes that, when inactivated, revealed determinants of sensitivity and resistance (Dataset S1). Here, CDADC1 is linked to acute lymphoblastic leukemia.