摘要: An analysis of BRCA1 and BRCA2 mutations in female relatives carriers identified among 1008 breast cancer patients has provided revised estimates for the risk associated with these mutations. In a Perspective, [Levy-Lahad Plon][1] discuss reported by New York Breast Cancer Study ([ King et al ][2].) what they reveal about influence nongenetic factors on susceptibility. [1]: http://www.sciencemag.org/cgi/content/full/302/5645/574 [2]: http://www.sciencemag.org/cgi/content/short/302/5645/643