Analysis of CRISPR/Cas9-mediated genome editing efficiency for knock-out manner in exogenous expression of RAD51. (A) Diagrams of CRISPR/Cas9-GFP and CRISPR/Cas9-RAD51-GFP vectors. (B) Schematic flow for delivery of CRISPR-Cas9 system to HEK293T cells using (A) modified vectors. (C) Schematic illustration of T7E1 assay to measure the genomic indel percentage. (D) T7E1 analysis comparing the generation of genomic modification at the target locus by the CRISPR/Cas9 system. Indel (%) was calculated as the intensity ratio of the digested band to the parental band.