After transducing PDX1 sgRNAs, we isolated GFP+ human islet cells 6 days after infection, and performed TIDE PCR and digital droplet (dd)PCR (Methods;27–29) with gene-specific probes to genomic DNA (Fig. 1C, D; n = 3 independent donors; Supplementary Fig. 2A, B). Here, PDX1 is linked to infection.