Rarity of "second-hit" inactivation of the involved gene in CHEK2-, NBN/NBS1- and BLM-associated BC demonstrates their substantial biological difference from BRCA1/2-driven cancers and makes them poorly suitable for the clinical trials with cisplatin and PARP inhibitors.
We tested the hypothesis whether three polymorphic, non-conservative amino acid exchanges in WRN and BLM act as low-penetrance familial breast cancer risk factors.