BRCA1 and breast cancer: By contrast, the four PALB2-associated breast cancers with mono-allelic inactivation (one ER−/HER2− and three ER+, sequenced by WES) displayed comparable LST scores to the 634 ER−/HER2− and ER+ non-BRCA1/2/PALB2-associated breast cancers for which LST scores could be defined (P > 0.05, Mann–Whitney U test and bootstrapping-corrected; Fig. 4c).