Gene Expression Test for CAD (IMAGE) University of California - Irvine Caption The gene expression test measures changes in blood cell RNA levels that are sensitive to the presence of coronary plaque. Credit CardioDx 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.