A University of Utah team of geneticists has found evidence that a condition associated with increased susceptibility to breast cancer is inherited.

The studies, researchers said, eventually could lead to tests enabling women with known breast cancer risks, based on their family histories, to be treated even before the smallest of tumors have formed.In an article published Friday in the journal Science, the team describes a study of 134 Utah women from 20 families.

Healthy women from families in which two family members had breast cancer were found to be about three times more likely than other women to have a non-malignant condition known as proliferative breast disease. This is a growth of cells that line the milk duct and may be a precursor lesion - meaning that in some cases breast cancer may develop.

"There are three stages of genetic research," said Dr. Mark H. Skolnick, a member of the Utah team. "First, researchers define an inheritance pattern of a condition within families. Next, they map or locate the gene causing the condition to a specific region of the chromosome. Finally, the gene is isolated, if possible."

Skolnick said the Utah study addresses the first stage of genetic research.

"We believe we have found an inheritance pattern for proliferative breast disease, an expression in the breast of a genetic predisposition to breast cancer."

He said more research must be done, however, before the geneticists understand the details of the condition.

"Based on this study, we believe the genetic susceptibility to breast cancer is more common than previously thought," Skolnick said. "We believe we have uncovered an important aspect of the development of breast cancer in families that carry a gene for proliferative breast cancer."