|How the CRISPR/Cas system works. Source.|
|Injection of vector into mouse tail veins directs|
DNA into the liver.
The authors also used this same method to cut out a normal version of beta-catenin, a gene that makes cells cancerous if additional mutations occur, with an overactive version of the same gene. This created a new mouse model for cancer research, in with a specific gene can be targeted and replaced in an adult! The success level was fairly low (0.5%), but this is a very promising start.
The authors hope that this method will help speed up cancer genomic research by bypassing the engineering of embryonic stem cells and then several generations of breeding to generate mutant lines. Ultimately, this can facilitate the study of any single genes or gene combinations that are suspected of initiating cancer formation in the liver. Given that cancer-causing genes are being found by the truckload thanks to next generation sequencing efforts, it's critical to find ways to quickly study them, and the results of this study are definitely moving cancer research in that direction. While this method has only been tested in liver cells, other delivery methods may be able to effectively target other organs.