(A) Expected GFP-hybridizing gDNA restriction fragment sizes for HR reporter at the ROSA26 locus. Upper panel: parental reporter; lower panel: “GFP triplication” outcome of LTGC. GFP copies within the reporter are shown. Filled ovals: artificial BsdR exons A and B. Restriction enzyme sites shown are SpeI (Sp), EcoRI (E), BamHI (B), HindIII (H) and SacI (Sa). Note that each of these restriction endonucleases, which cut target sites between the two GFP copies within the parental reporter, generate an additional 3.2kb GFP-hybridizing band in the context of the “GFP triplication” outcome. (B) Genomic DNA from parental and “GFP triplication” LTGC clones, as shown, was digested with the restriction enzymes shown (code as described above) and analyzed by Southern blotting (GFP probe). The 3.2kb amplification product characteristic of the “GFP triplication” LTGC outcome is marked with an arrowhead.