Mouse Embryo (IMAGE) Duke University Caption The human version of a DNA sequence called HARE5 turns on a gene important for brain development (gene activity is stained blue), and causes a mouse embryo to grow a 12 percent larger brain by the end of pregnancy than an embryo injected with the chimpanzee version of HARE5. Credit Silver lab, Duke University 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.