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Updated: Aug 12, 2026
08:53
Identifying the Effects of BRCA1 Mutations on Homologous Recombination using Cells that Express Endogenous Wild-type BRCA1
Published on: February 17, 2011
Structure and expression of variant BRCA2a lacking the transactivation domain
J P Zou1, Y Hirose, H Siddique
1Division of Cancer Genetics, Department of Human Genetics, MS 481, Allegheny University of the Health Sciences, Broad and Vine, Philadelphia, PA 19102, USA.
Oncology Reports
|February 19, 1999
Summary
Researchers discovered a new BRCA2 variant protein, BRCA2a, which lacks a transcriptional activation domain. This finding suggests BRCA2a and BRCA2 may play roles in thymus, testis, mammary gland, and prostate development and differentiation.
Area of Science:
- Genetics
- Molecular Biology
- Cancer Research
Background:
- BRCA1 and BRCA2 are critical tumor suppressor genes implicated in familial breast, ovarian, and prostate cancers.
- Both BRCA1 and BRCA2 gene products are cell cycle-regulated and possess transactivation functions.
Purpose of the Study:
- To investigate the functional implications of BRCA2 alternative splicing.
- To identify and characterize novel BRCA2 protein variants.
Main Methods:
- Analysis of BRCA2 gene splicing patterns.
- Protein expression analysis in various human tissues.
Main Results:
- Identification of a novel BRCA2 variant protein, termed BRCA2a, resulting from differential splicing.
- BRCA2a lacks a putative transcriptional activation domain found in the canonical BRCA2 protein.
- Both BRCA2a and BRCA2 are highly expressed in thymus and testis, and moderately in mammary gland and prostate.
Conclusions:
- BRCA2 undergoes alternative splicing, producing functionally distinct protein variants.
- The differential expression patterns of BRCA2 and BRCA2a suggest their involvement in the development and differentiation of specific tissues, including reproductive organs and the mammary gland.
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