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).