This is an archive page. The links are no longer being updated.
Date: Tuesday, June 4, 1996 FOR IMMEDIATE RELEASE Contact: NCI Press Office (301)496-6641
Scientists from the National Institutes of Health (NIH) have completed the data collection phase of a local study in the Washington, D.C. Jewish community to see if a particular genetic alteration in the first identified breast cancer gene, called BRCA1, is associated with an increased risk of cancer.
The recruitment effort, which began on Feb. 26, was complete on April 30. A total of5,377 volunteers donated a blood sample from a finger-prick and filled out a brief family medicalhistory of cancer. Participants included Jewish men and women over the age of 21, with and without personal or family histories of cancer. The goal was to recruit 3,000-5,000 Ashkenazi Jews (Jews of European descent).
"We are very grateful to the enormous support of the Jewish community that allowed usto surpass our goal. We thank not only the study participants, but the countless individuals and organizations that set up the test sites, publicized the study, and encouraged friends and family members to participate," says Jeffery P. Struewing, M.D., a principal investigator from theGenetic Epidemiology Branch of the National Cancer Institute (NCI). The study involves scientists at both the NCI and the National Center for Human Genome Research (NCHGR).
Analysis of the data has begun and the results are expected to be available by the end ofthe year. DNA from the blood samples will be tested for specific BRCA1 alterations, including the alteration known as 185delAG. A preliminary study found that 1 percent of Ashkenazi Jews have this particular mutation, but it is not known to what degree having this mutation increases the chance of getting cancer. Breast, ovarian, prostate, and colon cancers are possibly associated with the alteration. By comparing the cancer histories of the relatives of persons with the alteration to the histories of the relatives of persons without the alteration, researchers can estimate the cancer risk.
"This study will provide important information that up to now has not been known," said Richard D. Klausner, M.D., director of the NCI. "We need to know whether a person who has an alteration in this gene has an increased risk of cancer, and if so, which kinds of cancer."
The NIH study is unusual in that volunteers from the general population will be tested foran alteration in a cancer-predisposing gene. Until now, studies of these gene alterations have involved families with a high incidence of cancer throughout several generations of family members. From these high-risk families, it is estimated that alterations in BRCA1 account for about half of inherited breast cancer, over three quarters of inherited breast/ovarian cancer syndrome, and perhaps some portion of inherited prostate and colon cancer.
The l85delAG is one of over 100 alterations in the BRCA1 gene observed in thehigh-risk families. In general, each mutation is unique to a particular family. However, a surprising observation made last year was that a large percentage of unrelated high-risk families with the 185delAG alteration were Ashkenazi Jewish. (Ashkenazi Jews comprise 90 percent of the estimated six million Jews in the U.S.) It was this observation, plus the fact that testing for one particular mutation is technically simple, that led Struewing and Lawrence C. Brody, Ph.D., of NCHGR's Laboratory of GeneTransfer to test for the l85delAG alteration in over 800 stored DNA samples from Ashkenaziindividuals, previously screened for Tay-Sachs and cystic fibrosis. These individuals were from the general population, and their cancer history is not known.
The unexpected high frequency of the alteration, 1 percent, was reported in the October issue of Nature Genetics and provided the impetus for Klausner to initiate the NCI study in the Washington, D.C. Jewish population. The 1 percent frequency is about eight times higher than the estimated frequency for BRCA1 mutations in the general U.S. population, and is higher than many genetic diseases for which routine screening is conducted.
Volunteers in the study will not receive their individual results but, if they request, will receive a summary of the overall results of the study when it is complete.
"If the results show that all people with this alteration have a high risk of cancer, we anticipate that separate follow-up studies will be offered in which participants can receive their test results. At that time, participants would receive information and counseling about the implications of the results before they decide whether to take the test," said Klausner. The Cancer Information Service (CIS), a program of the National Cancer Institute, provides a nationwide telephone service for cancer patients and their families, the public, and health care professionals. CIS information specialists have extensive training in providing up-to-date and understandable information about cancer and cancer research. They can answer questions in English and Spanish and can send printed material. In addition, CIS offices serve specific geographic areas and have information about cancer-related services and resources in their region.The toll-free number of the CIS is 1 800 4 CANCER (1 800 422 6237). People with TTY equipment may call 1 800 332 8615. This document is also available through the NCI's CancerFax and CancerNet services, and in the News Section of the PDQ database. To get the document from CancerFax, dial 301 402 5874 from the handset of your fax machine and follow the recorded instructions to receive the contentslist. Individuals who have access to the Internet may access the document on CancerNet, through an electronic mail (E-mail) service or via the National Institutes of Health (NIH) gopher. To getthe CancerNet contents list from the E-mail service, send an E-mail message that says "help" inthe body of the message to cancernet@icicc.nci.nih.gov. To get the document from CancerNetvia the NIH gopher, point your gopher client to gopher.nih.gov and look for CancerNet under"Health and Clinical Information." To get the document from NCI's PDQ database, access PDQNews on the National Library of Medicine's MEDLARS system or consult a medical librarian forassistance. Additional information on this and other research topics may be found on the homepage of the NCI's International Cancer Information Center's World Wide Web server located at wwwicic.nci.nih.gov.