BRCA1 and neoplasm: BRCA1 is a tumor suppressor gene that encodes a multi-domain protein of 1863 amino acid involved in a wide array of cellular pathways that maintain genomic stability, including DNA damage-induced cell cycle checkpoint activation, DNA damage repair, protein ubiquitination, higher chromatin hierarchical control as well as transcriptional regulation and apoptosis (Powell and Kachnic, 2003; Narod and Foulkes, 2004; Figure 1A).