BETHESDA, Md-Scientists from the National Cancer Institute have found a specific mutation, 185delAG, in the breast cancer 1 gene (BRCA1) in almost 1% of DNA samples from a study group of Eastern European (Ashkenazi) Jews. This is the first time that scientists have been able to show that the gene mutation is present at measurable levels not only in high-risk families but also in a specific group of the general population.

At a press conference, Donna Shalala, secretary of the US Department of Health and Human Services, said that "this exciting finding should allow us to move rapidly toward our goal of identifying high-risk women and helping them to prevent breast cancer before it strikes."

The study, an international collaboration between the National Center for Human Genome Research (NCHGR), the NCI, the Sarett Institute (Jerusalem), and the University of California, San Diego, involved 858 unrelated Ashkenazi Jews from the United States and Israel whose family or personal cancer histories were not known.

Eight (1%) of the individuals tested were found to have the 185delAG mutation. This rate of alteration in the BRCA1 gene is three times higher than all BRCA1 alterations combined in the general population. Scientists did not find the alteration in 815 other samples from individuals not selected for ethnic origins.

Dr. Jeffery Struewing, lead author of the report (Nature Genetics, October, 1995), cautioned that the results were too preliminary to recommend immediate BRCA1 testing for the nation's 5.5 million Ashkenazi Jews. However, NIH has announced plans to launch a series of clinical studies to evaluate cancer risk in Ashkenazi Jews bearing the mutation.