While there was little difference in the abundance of many non-targeting-control sgRNAs between days 0 and 14, sgRNAs targeting genes known to be essential in MCL, such as CCND127, SOX1128,29, genes in the BCR and NFκB pathways, or pan-dependent genes in many cancers were substantially depleted by at least twofold on day 14 (Fig. 1a, b, Supplementary Fig. 1a, b, and Supplementary Data 1). The gene discussed is BCR; the disease is mantle cell lymphoma.