Since ATM plays such a key role in the DDR, the anti‐tumor effects of multiple ATM inhibitors (ATMis) have been widely investigated in both cancer cells and mouse models.[3] Recently, we reported that knockout of both the Fanconi Anemia (FA)/BRCA pathway and ATM strongly inhibits end resection and generates toxic levels of NHEJ, thereby resulting in cellular death by synthetic lethality (SL). This evidence concerns the gene ATM and Friedreich ataxia.