This lab is easy for teachers to prepare, makes gene targeting accessible to students, and packs a powerful punch! Become a genetic engineer and use CRISPR/Cas to disable a gene in bacteria. Scientists use the CRISPR/Cas system to alter the DNA in living cells. Now you can bring this cutting-edge technique to your advanced biology class! In this lab, E. colicells which express the lacZ gene from a plasmid will be transformed with another plasmid containing the cas9gene and a custom guide RNA. This guide RNA contains a sequence complementary to the lacZ gene so, in transformed cells, the guide RNA will target Cas9 to cut the lacZ gene, disabling it. Students can easily identify their CRISPR/Cas knockouts using the color of the bacterial colonies. Cells which express lacZare able to break down the chemical X-gal into a blue product. Cells with a functional laczwill be blue, while cells in which the CRISPR/Cas system has successfully disabled lacZwill revert to a white phenotype. Note: This is a technically advanced lab that requires a 2-hour class period. Students should have prior experience with bacterial transformation. Techniques: Micropipetting, bacterial transformation, gene targeting Topics: Genome editing, biotechnology, molecular biology Time required: Requires a 2-hour class period Level: Advanced high school through college This product is sold for educational use only. It contains technologies that are owned and licensed for educational purposes only by miniPCR bio and by third parties, including Rockefeller University and the Broad Institute.