A Risky Business--Assessing Breast Cancer Risk

Abstract
An analysis of BRCA1 and BRCA2 mutations in female relatives of carriers identified among 1008 breast cancer patients has provided revised estimates for the breast cancer risk associated with these mutations. In a Perspective, Levy-Lahad and Plon discuss these revised estimates reported by the New York Breast Cancer Study ( King et al .) and what they reveal about the influence of nongenetic factors on breast cancer susceptibility.