Compared to other genes implicated in HR and PARP inhibitor sensitivity, CBLC mutations are relatively rare in cancer, being present in approximately 2 % of 4000 human tumours whose exome sequence is described on the cBio database [30, 31] This of course does not exclude the possibility that impaired CBLC transcription, translation or reduction in CBLC protein levels by enhanced turnover could cause sensitivity to a PARP inhibitor. Here, PARP1 is linked to cancer.