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

Abstract

Gardner's syndrome is an autosomal dominant disorder that predisposes to cancer of the large intestine and to other tumors. We have previously demonstrated that fibroblasts from a patient with this disease are hypersensitive to the cytotoxic effects of ultraviolet light. In this report we have measured several parameters of the repair of ultraviolet light-induced DNA damage in an attempt to identify a defect responsible for the hypersensitivity. We 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.