The most recent issue of Science was partly dedicated to articles on breast cancer research. One article by authors Couch, Nathanson & Offit reviewed how genetic testing in breast cancer has developed over the past twenty years. They discuss the clinical advancements made from identifying inherited mutations and sequence variants in BRCA1 and BRCA2 and the complexities of determining disease risk when the pathogenicity of sequence variants is uncertain. Many variants of uncertain significance, including missense, intronic and small in-frame insertion/deletion variants, are observed at the BRCA1/2 loci. Current clinical management of breast cancer includes gene expression microarrays to subclassify the disease and serve as prognostic biomarkers, as well as targeted therapy for breast cancers over-expressing the HER2/neu receptor. The evolution of clinical treatment for breast cancer is an example of how genetic testing is a burgeoning field and will allow for more personalized care in the future.