Excision repair defect in Rothmund Thomson syndrome

Rothmund Thomson syndrome is a rare autosomal recessive skin disorder. The main clinical feature is poikiloderma appearing in early childhood associat ed with skeletal abnormalities. Early occurrence of malignancies is another relevant feature. Here we describe the clinical features of 2 patients wit h Rothmund Thomson syndrome who were investigated for the in vitro DNA repa ir capacities of blood cells following UVC radiation exposure. DNA excision repair, assessed with unscheduled DNA synthesis following UVC exposure, wa s decreased in both patients, Such a defect might explain the patients' sen sitivity to sunlight and the relatively high risk of cancer associated with this syndrome.