CRISPR-Cas9 has become the most widely used genome editing tool since Jennifer Doudna and Emmanuelle Charpentier demonstrated its programmability in 2012, earning them the 2020 Nobel Prize in Chemistry. The system consists of two components: the Cas9 protein, which acts as molecular scissors, and a guide RNA that directs Cas9 to a specific genomic location through Watson-Crick base pairing. This elegant simplicity, replacing complex protein engineering with a short RNA sequence to retarget the nuclease, democratized genome editing across laboratories worldwide.
The commercial ecosystem around CRISPR-Cas9 has grown rapidly. Mammoth Biosciences, co-founded by Doudna, is developing ultra-compact Cas proteins and diagnostic applications. CRISPR Therapeutics, co-founded by Charpentier, partnered with Vertex Pharmaceuticals to bring Casgevy to market as the first approved CRISPR therapy for sickle cell disease and transfusion-dependent beta-thalassemia. Intellia Therapeutics and Editas Medicine are advancing additional CRISPR-Cas9-based therapies through clinical trials for conditions including transthyretin amyloidosis and Leber congenital amaurosis.
Beyond therapeutics, CRISPR-Cas9 has transformed research in agriculture, industrial biotechnology, and functional genomics. High-throughput CRISPR screens enable systematic interrogation of gene function at genome scale, while multiplexed editing allows simultaneous modification of many genes. Companies like Synthego provide engineered guide RNAs and ribonucleoprotein complexes that have standardized CRISPR reagent delivery, making precise genome editing accessible to any laboratory with basic molecular biology capabilities.