Comparison_between_full_length_and_trancated_CRISPR_guide_RNAs

The CRISPR-Cas system is a new DNA-editing technology and promise potential in many applications such as genome engineering and genetic screening. One issues associsted with this technology is off-target cleavage, which may cause unwanted phenotypic outcome. Guiding sequence in guide RNA is typically 20-bp in length. Recently, truncated guide RNA, which is 19-17 bp in lenth, has mich higher specificity and therefore significantly reduce off-target cleavage. These experiments were performed in transient transfection system. Here we generated cancer cell lines stably expressing both Cas9 and guid RNAs in a full-length or truncated form. We will measure off-target cleavage in these cell lines.