In this study, the colony-forming assay and Western blot analysis of the DNA repair proteins hMre11, Rad50 and Rad51 did not reveal any abnormalities in cellular radiosensitivity in vitro and in expression levels or migration patters of these proteins in the fibroblasts derived from the cancer patients with increased early reaction of normal tissue to radiotherapy. The gene discussed is XRCC6P5; the disease is cancer.