Targeted sequencing of BRCA1 and BRCA2 across a large unselected breast cancer cohort suggests that one-third of mutations are somatic

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Targeted sequencing of BRCA1 and BRCA2 across a large unselected breast cancer cohort suggests that one-third of mutations are somatic

( Somatic mutation, genetic alteration acquired by a cell that can be passed to the progeny of the mutated cell in the course of cell division. Somatic mutations differ from germ line mutations, which are inherited genetic alterations that occur in the germ cells (i.e., sperm and eggs).)
 

For relapsed ovarian cancer, the PARP inhibitor olaparib has recently been approved in Europe for use in patients with BRCA1/2 mutations—regardless of the mutations being germline or somatic [15, 16]. Ongoing trials will determine whether this will be the case also for breast cancer patients [17].

 In conclusion, in our data from a population without strong germline founder mutations, the likelihood of a BRCA1/2 mutation found in a breast carcinoma being somatic was ∼1/3 and germline 2/3. This could have implications for treatment and genetic counseling.