 XRCC1 is involved in single-strand break repair, base excision repair and nucleotide excision repair.As reviewed by London, XRCC1 protein has three globular domains connected by two linker segments of ~150 and 120 residues.The XRCC1 N-terminal domain binds to DNA polymerase beta, the C-terminal BRCT domain interacts with DNA ligase III alpha and the central domain contains a poly(ADP-ribose) binding motif.