RAD51 and breast carcinoma: It leads to formation of a structure called 3′overhang, which is stabilized by RPA (replication protein A) and then loaded on the homologous DSB region by the strand exchange protein RAD51 (RAD51 recombinase) and by BRCA2 (breast cancer 2, DNA repair associated), resulting in the formation of the Holliday junctions intermediate.