In several tumors, loss of wild-type p53 or ATM function can sensitize cancer cells to Olaparib [34–36], as well as CCDC6 deficiency that affect the DSBs DNA repair by homologous recombination can sensitize the tumor cells to PARP-inhibitors, that act synergically with genotoxic agent [12, 16]. The gene discussed is ATM; the disease is cancer.