WASHINGTON -- U.S. scientists have identified a gene, the absence or inactivity of which, was found to be associated with nonhereditary breast cancer, according to a study published Monday.

More than 90 percent of breast cancer is not hereditary.

Researchers discovered a particular gene was missing in 60 percent of the breast cancer cases examined. The gene is one of the first to be identified with tumor suppression.

The absence of the gene, labeled DBC2 (for "deleted in breast cancer"), could also play a role in certain cases of lung cancer, according to the study to be published in the October 15 edition of the **** Proceedings of the National Academy of Science ****.

Researchers at Cold Spring Harbor Laboratory in New York and the University of Washington, in Seattle, Washington, showed that the production of DBC2 in cancerous cells in the breast killed the cells or stopped the cancer's progression.

Michael Wigler's team in New York also identified the only other gene associated with nonhereditary breast cancer in 1997.

In 1990, the Washington State team under the direction of Mary-Claire King, identified the first gene linked to hereditary breast cancer.

Since then researchers have identified a total of eight genes that play a role in the development of hereditary breast cancer. But this type of breast cancer makes up only 10 percent of overall cases.

According to AFP breast cancer kills 400,000 women worldwide each year, and 800,000 more cases are diagnosed annually. It is the second leading cause of death from cancer for women after lung cancer.