Variation of breast cancer risk among BRCA1/2 carriers
CONTEXT: The risk of breast cancer in BRCA1 and BRCA2 mutation carriers has been examined in many studies, but relatively little attention has been paid to the degree to which the risk may vary among carriers. OBJECTIVES: To determine the extent to which risks for BRCA1 and BRCA2 carriers vary with respect to observable and unobservable characteristics. DESIGN, SETTING, AND PARTICIPANTS: Probands
