CRISPR-Cas9 (IMAGE) Rice University Caption When a CRISPR-Cas9 protein finds its target, it first finds a spacer sequence known as PAM and then searches adjacent DNA to see if it matches Cas9's guide RNA. A new model developed by researchers at Rice University could help uncover details about the mechanism by which CRISPR-Cas9 can replace mutations with correct DNA. Credit Alexey Shvets/Rice University Usage Restrictions For news reporting purposes only. 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.