In the study the team led by scientists at University of Texas-San Antonio used nanoparticle carriers to inject a gene-editing enzyme called Cas9 into the striatum -- a brain region associated with formation of habits. Enzymes are proteins that trigger biochemical reactions. The enzyme we used Cas9 is like a pair of scissors. We were able to cut the genetic blueprint DNA at a location that causes the exaggerated repetitive behaviours said Hye Young Lee Assistant Professor at the varsity. In a mice model with fragile X syndrome -- an inherited cause of autism spectrum disorders the researchers targeted Cas9 at
