Genetics and Breast Cancer by Henry T. Lynch MD. Breast cancer is one of the leading killers of women in the US today. A high proportion of these cases occur in genetically predisposed members of certain families. Environmental, lifestyle, and other factors are believed to trigger and hasten the onset of this disease of those having the proper genetic predisposition . This timely reference uniquely integrates epidemiology , biostatistics, genetics ,pathology, endocrinology, and clinical medicine in concert with hereditary breast cancer.