XRCC3 and breast neoplasm: Indeed, the size distribution of deletions and the presence of a few other types of non-clustered rearrangements in RAD51C−/−, XRCC2−/−, XRCC3−/−, BRCA2−/−, or PALB2−/− mutant cells closely resembled the predominant rearrangement signature of BRCA2-deficient breast tumors (Fig. 4d).