Enhanced DNA-Repair Mechanism can Cause Breast Cancer, University of Chicago Study

Although defects in the "breast cancer gene," BRCA1, have been known for years to increase the risk for breast cancer, exactly how it can lead to tumor growth has remained a mystery. In the October 15, 2007, issue of the journal Cancer Research, scientists from the University of Chicago and Kyoto University, Japan, suggest that a mechanism that normally repairs damaged DNA may function abnormally in BRCA1 carriers leading to one type of poor-prognosis breast cancer. Their findings provide insight into how the normal BRCA1 gene suppresses the growth of tumors as well as the nature of the genetic instability that leads to cancer when BRCA1 is defective.