Dr Oana Ursu is a postdoctoral researcher working with Dr Aviv Regev at Genentech. Oana’s research is focused on learning how cells make decisions about their internal states, and how they transition between these states, using pooled high-content screens with single-cell readouts. Oana is particularly interested in cell state changes occurring as cells develop resistance to cancer therapies, and in the role of chromatin and gene regulation in allowing cells to survive different treatments. In her talk, Oana will describe efforts in collaboration with JT Neal and Jesse Boehm’s groups at the Broad Institute to study coding variants in cancer, towards mapping their roles for tumor biology and ultimately drug response. This work uses single-cell screening technologies based on Perturb-seq to distinguish between impactful coding variants with key roles in cancer and more inert passenger mutations, with a proof of concept characterization of two hundred variants in the TP53 and KRAS genes.