The BCDX2 complex, composed of RAD51 paralogs RAD51B, RAD51C, RAD51D and XRCC2, preferentially binds at the ends of 3' overhanging ssDNA created by resection of DNA double strand breaks (DSBs). The BCDX2 complex stabilizes nucleoprotein filaments formed by BRCA2-mediated RAD51 loading onto ssDNA (Masson et al. 2001, Chun et al. 2013). The BCDX2 complex may act by inhibiting displacement of RAD51 by BLM helicase (Amunugama et al. 2013).