Loss of function mutations in BRCA1 (nonsense, frameshift, splice site, and exonic deletions) as well as whole gene deletions of BRCA1 have been associated with cancer development (Genereviews and PMIDs: 21989022, 17661172, and 22762150). The penetrance associated with BRCA1 mutations is still an active area of study; however, patients with pathogenic BRCA1 mutations are thought to have an increased lifetime risk of developing breast cancer (50-80% in females, 1-2% in males), ovarian cancer (24-40%), prostate cancer (up to 30%), and pancreatic cancer (1-7%) (Genereviews Table 3).
At this time there is no evidence to support the triplosensitivity of this gene.