 At the cellular level, disruption of XRCC4 induces hypersensitivity to agents that induce double-strand breaks, defective double-strand break repair and increased apoptosis after induction of DNA damage.Anti-XRCC4 antibodies including phosphospecific antibodies to pS260 and pS318 in XRCC4 have been developed.Antibodies to XRCC4 can have a variety of uses, including use in immunoassays to conduct research in areas such as DNA damage and repair, non-homologous end joining, transcription factors, epigenetics and nuclear signaling.