Nat. Biomed. Eng. https://doi.org/10.1038/s41551-018-0252-8 (2018).

To get CRISPR-Cas9 where it needs to be to realize its gene-editing potential, most approaches uses viral vectors to deliver the tool, its machinery, and the corrected donor sequence to the right location. But viruses can trigger immune reactions, and viral vectors can lead to toxic overexpression of the molecular scissor. Last year, researchers at the University of California Berkeley created a non-viral delivery vehicle that employs gold nanoparticles to transport the necessary components and used it to improve the symptoms of mouse models of Duchene muscular dystrophy (Nat. Biomed. Eng. 1, 889–901; 2017). A new paper takes the CRISPR-Gold approach to the sensitive and tricky-to-access mouse brain, demonstrating biocompatibility, editing potential in both neurons and glial cells, and efficacy in reducing repetitive behaviors in mice modeling fragile X syndrome.