Loose End after Cas9 binding (IMAGE) University of California - Berkeley Caption A view of the Cas9 protein (red and blue) bound to a double strand of DNA (purple and grey). After both strands are cut, one DNA strand (purple dots) is free and able to bind with a piece of DNA to be inserted at the break.This behavior can be utilized to significantly boost the efficiency of gene editing. Credit Christopher Richardson, UC Berkeley Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.