Active 'Jumping Genes' Cause Genetic Damage and Severe Developmental Defects (image) Cold Spring Harbor Laboratory Share Print E-Mail Caption "Jumping genes" or transposable elements are long stretches of repetitive DNA that can insert themselves throughout the genome. Normally, they are held inactive by a series of marks along the genome. But when these marks are erased, activated transposons can disrupt critical genes, causing dramatic defects in development. Here are two flowers: on the left is a normal plant where transposons are silent; on the right, transposons have been activated, severely mutating the flower. Researchers at CSHL have discovered a new fail-safe mechanism that prevents transposon activation even when the inactivating marks have been erased. Credit Rob Martienssen, Cold Spring Harbor Laboratory Usage Restrictions None Share Print E-Mail 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.