CRISPR-Cas9 gene editing. Diagram of the process that occurs within the CRISPR-Cas9 gene editing complex. This protein (purple) is used in genome engineering to cut DNA (deoxyribonucleic acid). It uses a guide RNA (ribonucleic acid) sequence (green) to cut DNA (blue) at a complementary site. The cut area of DNA is shown in yellow. The process of inserting a fragment of donor DNA (red) is shown at lower centre, with a genetically modified laboratory mouse at bottom. CRISPR (Clustered Regularly Interspersed Palindromic Repeats) is a bacterial adaptive immunity system. Unlabelled version: C029/2554.