A mouse embryo (IMAGE) Ecole Polytechnique Fédérale de Lausanne Caption A mouse embryo Credit Denis Duboule (EPFL/UniGe) Usage Restrictions Media purposes only. Commercial usage restricted; by permission only. License Original 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.