American human geneticist Mary Claire King (1946–) determined that in 5 to 10 percent of those women with breast cancer, the cancer is the result of a mutation of a gene on chromosome 17, the BRCA1 (Breast Cancer 1). The BRCA1 gene is a tumor suppressor gene and is also linked to ovarian cancer. Subsequently, other researchers were able to clone the gene and pinpoint its exact location on chromosome 17.