BRCA2 and breast neoplasm: Additionally, a rather uniform mutational signature (no prominent features across trinucleotides) was also identified and, interestingly, the activity of this mutational signature in each of the 21 samples allowed separation (by unsupervised hierarchical clustering) of BRCA1 and BRCA2 wild-type breast tumours from BRCA1 and BRCA2 germline mutants.