 Based on the findings that (1) several polypeptides in the NHEJ pathway are "potential targets of autoantibodies" and (2) "one of the autoimmune epitopes in XRCC4 coincides with a sequence that is a nexus for radiation-induced regulatory events", it has been suggested that exposure to DNA double-strand break-introducing agents "may be one of the factors" mediating autoimmune responses.There has been speculation that "XRCC4 codon 247*A and XRCC4 promoter -1394*T related genotypes and alleles ..