SRP341493 PRJNA771464 PEM-seq data of eeCas9 and eeBE To further evaluate the specificity of eeCas9 at whole-genome-wide level,we performed primer-extension-medicated sequencing (PEM-seq), a high-throughput sequencing method via capturing the off-target sites translocated with on-target site, to detect the number of off-target sites caused by Cas9 or eeCas9 nuclease.