PURPOSE: The goal of the Metropolitan NY Registry, and five other international collaborating sites of the Cooperative Family Registry for Breast Cancer Studies [CFRBCS], has been the development of a comprehensive resource for interdisciplinary genetic epidemiology studies addressing breast cancer risk and prognostic factors.METHODS: Family recruitment has been conducted in clinical and community settings by a multidisciplinary team of collaborators affiliated at six major metropolitan NY medical centers. Families meeting one of the following criteria were invited to join: a male with breast cancer; a female with breast or ovarian cancer diagnosed at age </=45; a female with breast and ovarian cancer; or two or more first and second degree relatives diagnosed at any ages. Participants are asked to complete an epidemiology questionnaire, dietary history form, extensive family history, and donate biospecimens including blood and urine. Pathology reports and tissue samples are obtained for breast and ovarian cancer cases; pathology reports are requested to confirm the history of other cancers.RESULTS: Of the 1102 families (3,252 participants), 28 males and 1,304 females had been treated for breast cancer. More than 2,400 blood samples are banked and >3,000 epidemiology questionnaires completed. Ethnic/racial data indicates 14% are of African American or Hispanic heritage and 509 families (46%) are of Ashkenazi descent. One or more DNA samples from 400 Ashkenazi families have been tested for the three BRCA1/2 founder mutations. Of 331 Ashkenazi participants with a history of breast and/or ovarian cancer, 19% were found to be mutation carriers. Thirty-six (7 men/29 women) mutation carriers are free of cancer.CONCLUSIONS: The families participating in the NY Registry reflect a spectrum of breast cancer risk. The extensive NY and CFRBCS databases and banked biospecimens provide a unique resource for multidisciplinary genetic epidemiologic studies that may identify avenues for prevention.