For example, an enzyme in the alt-EJ pathway, Polυ, can inhibit HR pathway activity through binding with RAD51, indicating that Polυis vital for alt-EJ to compete with the HR pathway.340 In contrast, HR factors such as FA (Fanconi anemia) proteins also promote alt-EJ activity,341 suggesting that these factors, which interact with ATM and RAD51, can influence repair pathway selection in a background-dependent manner.97,342 In general, these studies confirm that multiple connections exist between alt-EJ and HR. This evidence concerns the gene RAD51 and Fanconi anemia.