BRCA1 and neoplasm: Along with having high mutational loads, DNA damage response (DDR)-deficient tumours may also have unique immunological characteristics and at least BRCA1/2 mutant tumours have been shown to be associated with higher levels of TILs, increased secretion of lymphocyte attractants (eg, C-X-C motif ligand (CXCL) 10 (CXCL10)) and upregulation of immune suppressive ligands such as PD-L1 (Mulligan et al, 2013; Strickland et al, 2016).