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Low-level constitutional mosaicism of a de novoBRCA1 gene mutation.

ABSTRACT:

Background

Pathogenic BRCA1 mutations are usually inherited. Constitutional low-level BRCA1 mosaicism has never been reported.

Methods

Next-generation sequencing (NGS) of cancer gene panel of germline and tumour DNA in a patient with early onset, triple-negative breast cancer.

Results

Constitutional de novo mosaicism (5%) for a pathogenic (c.1953dupG; p.Lys652Glufs*21) BRCA1mutation was detected in leukocytes, buccal tissue and normal breast tissue DNA, with ∼50% mutation in tumorous breast tissue.

Conclusion

This is the first reported case of low-level, multiple tissue, constitutional mosaicism in BRCA1, and highlights the need to consider deep sequencing in affected individuals clinically suspected of having cancer predisposition whose tumours display a BRCA mutation.

SUBMITTER: Friedman E

PROVIDER: S-EPMC4333503 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Low-level constitutional mosaicism of a de novoBRCA1 gene mutation.

Friedman E E Efrat N N Soussan-Gutman L L Dvir A A Kaplan Y Y Ekstein T T Nykamp K K Powers M M Rabideau M M Sorenson J J Topper S S

British journal of cancer 20150129 4

<h4>Background</h4>Pathogenic BRCA1 mutations are usually inherited. Constitutional low-level BRCA1 mosaicism has never been reported.<h4>Methods</h4>Next-generation sequencing (NGS) of cancer gene panel of germline and tumour DNA in a patient with early onset, triple-negative breast cancer.<h4>Results</h4>Constitutional de novo mosaicism (5%) for a pathogenic (c.1953dupG; p.Lys652Glufs*21) BRCA1mutation was detected in leukocytes, buccal tissue and normal breast tissue DNA, with ∼50% mutation i ...[more]

PMID: 25633036

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