Fig. 1

ZFN and sgRNA design and detection of targeted cutting activities. a Schematic diagram of the target sites of the designed sgRNA and the ZFN pair in the human CCR5 gene. The green arrow indicates the sequence used for the guide segment of sgRNA. The NGG nucleotide protospacer adjacent motif (PAM) sequences are shown in red and are underlined. The binding sites of the ZFN pair (ZFN-L and ZFN-R) are marked by blue boxes. b The frequency of CRISPR/Cas9- and ZFN-induced mutations as determined by the T7E1 assay. The numbers at the bottom of the gel indicate the mutation percentages estimated based on band intensities measured using ImageJ. NC represents negative control. c DNA sequences of the wild-type (WT) and mutant clones. The target sites of the ZFN pair and sgRNA are shown in yellow and green bars, respectively. The PAM sequence is shown in red and underlined. Dashes and blue letters represent deleted and inserted bases, respectively. The number of inserted or deleted bases and the ratio of the number of mutant clones to the number of total clones are indicated in the parentheses. Mutation frequencies were obtained by dividing the total number of mutant clones by the number of total clones