Circadian clock (IMAGE) University of Chicago Medical Center Caption DNA replication cycles are tied to the circadian clock, and interruptions can lead to incomplete chromosomes. Credit Image courtesy of Yi Liao. Usage Restrictions May only be used for reporting this specific story 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.