%0 Journal Article %A Rolen M. Quadros %A Masato Ohtsuka %A Donald W Harms %A Tomomi Aida %A Ronald Redder %A Hiromi Miura %A Guy P. Richardson %A Mark A. Behlke %A Sarah A. Zeiner %A Ashley M. Jacobi %A Lisa D. Urness %A Suzanne L. Mansour %A Channabasavaiah B. Gurumurthy %T Easi-CRISPR: Efficient germline modification with long ssDNA donors %D 2016 %R 10.1101/069963 %J bioRxiv %P 069963 %X CRISPR/Cas9 technology efficiently produces short insertions or deletions (indels) and can insert short exogenous sequences at Cas9 cut sites. However, targeting long inserts is still a major technical challenge. To overcome this challenge, we developed Easi-CRISPR (Efficient additions with ssDNA inserts-CRISPR), a method that uses long, in vitro-synthesized, single-stranded DNAs with 50-100 base homology arms as repair templates. We demonstrate that Easi-CRISPR can generate knock-in and floxed alleles in mice with an efficiency at many loci as high as 100%. The simple design requirements for donor DNAs and the reproducibly high-efficiency of Easi-CRISPR enables rapid development of many types of commonly used animal and cell models. %U https://www.biorxiv.org/content/biorxiv/early/2016/08/17/069963.full.pdf