This work is part of the joint research project 'radiation-induced DNA damage' of the KVSF, a BMBF Initiative (maintenance of radiation biology expertise in Germany). The focus of the research is the mechanism of DNA repair, specifically damage repair aspects arising from radiation-induced reactive oxygen species production. The authors will systematically look at potential accessory proteins associated with primarily base excision repair using molecular and biochemical methods. The authors hope to gain knowledge on the initial response mechanisms to varying sources and doses of radiation. By using a highly sensitive marker system, it is intended to achieve a greater resolution of responses induced at lower doses. The work is of relevance for different human diseases caused by defects in DNA repair, e.g. spontaneous and radiation-related cancer. Beyond this, the risk of low radiation doses, for example, in the workplace is of relevance for radiation protection policy and decision-making thereof.