The 3,500-word paper went into great detail on how the crRNA and the tracrRNA worked to bind the Cas9 protein onto the target DNA. It also showed how the structure of two Cas9 domains determined how each cut one of the DNA strands at a specific location. Finally, it described how they were able to fuse the crRNA and tracrRNA to engineer a single-guide RNA. This system, the authors noted, could be used to edit genes.
