That the prevalence of reversion mutations in our study were on the lower end of the spectrum of that previously observed may reflect that there were more tumours from this cohort associated with BRCA1 mutations rather than BRCA2, as previous studies have shown a trend (albeit not statistically significant) towards reversions being more prevalent in BRCA2 mutant tumours18,21. This evidence concerns the gene BRCA2 and neoplasm.