[Is hereditary predisposition to breast cancer linked to BRCA1 a disease of response to genotoxic lesions?].

Germline mutations in either the BRCA1 or the BRCA2 gene are responsible for the majority of hereditary breast cancers. The proposition that BRCA1 may play a role as a caretaker of the genome, was first put forward by the demonstration that, in mitotic and meiotic cells, BRCA1 can interact with Rad51, a major actor in repair and/or recombination processes. From there, a fair body of observations have converged to support the concept that BRCA1 and BRCA2 play a role in monitoring and/or repairing DNA lesions. The relaxation in this monitoring, due to mutations of either of these two genes, leaves unrepaired events and leads to the accumulation of mutations and ultimately to cancer. Understanding the precise biochemical function of BRCA1 and BRCA2 should provide basis for early diagnosis and prevention in women carrying a predisposition to breast cancer.