BRCA1 and BRCA2: from molecular genetics to clinical medicine.

Inherited susceptibility to breast cancer has been an area of intense investigation for the past 10 years. Early work focused on identifying modes of transmission, which culminated in the identification of chromosome 17q12-21 as the first human genomic region that harbored an autosomal dominant susceptibility gene for breast cancer (BRCA1) in 1990. BRCA1 was subsequently identified and was followed shortly by the identification of BRCA2. Research in the past 3 years has elucidated much about the mutation spectrum and mutation frequency of these genes in specific populations and is beginning to identify potential functions. Whereas progress in this area has been rapid and much is now known about inherited susceptibility to breast cancer, much more needs to be done to make these discoveries useful in the diagnosis, treatment, and ultimately, the prevention of breast cancer.