Sister chromatid exchange frequencies in patients with scleroderma and their relatives.

Sister chromatid exchange (SCE) analysis is a sensitive measure of chromosome damage induced by many agents which damage DNA. These agents have been reported to be present in the serum of patients with scleroderma. Chromosome aberrations are thought to be more common in cells of these patients and their relatives than in cells of controls. We have observed that the SCE frequencies in blood lymphocytes of patients with scleroderma and their relatives do not differ from those of controls.