Oocyte with Decreased Topoiosmerase II (IMAGE) Stowers Institute for Medical Research Caption An oocyte with decreased Topoiosmerase II levels in heterochromatic region of the X chromosome (green) failed to separate while heterochromatic region of the 4th chromosome (red) is stretched into abnormal projections. Credit Stacie Hughes, Ph.D., Hawley Lab, Stowers Institute for Medical Research 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.