Ku70, known by several synonyms including X-ray repair cross-complementing, 5'-deoxyribose-5-phosphate lyase Ku70 protein 6, 70 kDa subunit of Ku antigen, XRCC6, and G22P1, is a 70 kDa protein that was shown to be involved in multiple cellular pathways, mainly involving DNA repair and recombination (2).
Originally identified as autoantigens from a Scleroderma Polymyositis Syndrome patient (1), the Ku protein family consists of nuclear proteins found in eukaryotes. Autoantibodies to both Ku subunits were subsequently found in other autoimmune diseases such as Systemic Lupus Erythematosus.
