Dr. David Euhus (IMAGE) UT Southwestern Medical Center Caption Dr. David Euhus has helped determine that methylation acts as a type of biological clock, indicating how many times a cell has divided. The chemical reaction in genes could one day help researchers more accurately determine a woman’s risk for developing breast cancer and provide a new approach for treatment. Credit UT Southwestern Medical Center Usage Restrictions Please use our credit line. 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.