Although a specific gene responsible for the familial breast cancer is not discovered yet mutations in some suppressor genes such as BRCA1, BRCA2, ATM, PTEN, TP53, BRIP1, PALB2, NBS1, RAD50, MSH2, MLH, and CHEK2 are occurred in about half of the familial breast cancer (Walsh and King, 2007). The gene discussed is ATM; the disease is hereditary breast carcinoma.