An analysis of 1,600 European women with genetic mutations that predispose them to breast cancer suggests mammogram X-rays might increase that risk.

The study also suggests X-ray exposure before the age of 20 might cause a particularly heightened risk.

The research is the first to analyze the impact of low-level X-ray exposure among women at genetically high risk for the disease.

"If confirmed in prospective studies, young women who are members of families known to have BRCA1 or BRCA2 mutations may wish to consider alternatives to X-ray, such as MRI," said David Goldgar, lead author of the study who was the chief of the genetic epidemiology group at the International Agency for Research on Cancer in Lyon, France, when the research was conducted.

Women with the mutations who reported having a chest X-ray were found 54 percent more likely to develop breast cancer than women who never underwent the procedure. In addition, women exposed to X-rays before age 20 had a 2.5 times increased risk of developing the disease before age 40, compared with women who had never been exposed.

The study appears in the Journal of Clinical Oncology.

Copyright 2006 by United Press International