Mapping Genetic Interactions in Human Cancer Cells Using a One-Step tRNA-CRISPR System.

While well studied in yeast, mapping genetic interactions in mammalian cells has been limited due to many technical obstacles. We have recently developed a new one-step tRNA-CRISPR method called TCGI (tRNA-CRISPR for genetic interactions) which generates high-efficiency, barcode-free, and scalable pairwise CRISPR libraries to identify genetic interactions in mammalian cells. Here we describe this method in detail regarding the construction of the pairwise CRISPR libraries and performing high throughput genetic interacting screening and data analysis. This novel TCGI dramatically improves upon the current methods for mapping genetic interactions and screening drug targets for combinational therapies.