%0 Letter %T Guide for generating single cell-derived knockout clones in mammalian cell lines using the CRISPR/Cas9 system. %A Hong T %A Bae SM %A Song G %A Lim W %J Mol Cells %V 0 %N 0 %D 2024 Jun 25 %M 38936509 %F 4.25 %R 10.1016/j.mocell.2024.100087 %X Genome editing has developed rapidly in various research fields for targeted genome modifications in many organisms, including cells, plants, viruses, and animals. The CRISPR/Cas9 system stands as a potent tool in gene editing for generating cells and animal models with high precision. The clinical potential of CRISPR/Cas9 has been extensively reported, with applications in genetic disease correction, inhibition of viral replication, and personalized or targeted therapeutics for various cancers. In this study, we provide a guide on single guide RNA (sgRNA) design, cloning sgRNA into plasmid vectors, single-cell isolation via transfection, and identification of knockout clones using next-generation sequencing. In addition, by providing the results of insertion into mammalian cell lines through next generation sequencing (NGS), we offer useful information to those conducting research on human and animal cell lines.