Allen Institute for Cell Science 1 article published in JoVE Genetics Endogenous Protein Tagging in Human Induced Pluripotent Stem Cells Using CRISPR/Cas9 Amanda Haupt1, Tanya Grancharova1, Joy Arakaki1, Margaret A. Fuqua1, Brock Roberts1, Ruwanthi N. Gunawardane1 1Allen Institute for Cell Science Described here is a protocol for tagging endogenously expressed proteins with fluorescent tags in human induced pluripotent stem cells using CRISPR/Cas9. Putatively edited cells are enriched by fluorescence activated cell sorting and clonal cell lines are generated.