Gradient Indicating Epistatic Variance in 2-Gene System (IMAGE) Institute of Science and Technology Austria Caption This gradient indicates the epistatic variance in a two-gene system. Credit © Tiago Paixao 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.