Normal repair of ultraviolet-induced DNA damage in a hypersensitive strain of fibroblasts from a patient with Gardner's syndrome

Gardner's syndrome is an autosomal dominant disorder that predisposes to cancer of the large intestine and to other tumors. It was previously demonstrated that fibroblasts from a patient with this disease are hypersensitive to the cytotoxic effects of ultraviolet light. In this report the authors have measured several parameters of the repair of ultraviolet light-induced DNA damage in an attempt to identify a defect responsible for the hypersensitivity. They have found the excision rate of pyrimidine dimers, the host cell reactivation of UV-irradiated herpes simplex virus, the induction and rejoining of DNA single strand breaks and the response of semi-conservative DNA replication to UV-irradiation to be in all cases indistinguishable from such phenomena in a variety of normal cells. (Auth.)