title: Cockayne syndrome: a cellular sensitivity to ultraviolet light.
abstract: Two unrelated children, a boy 2 1/2 years old and a girl 4 years old, were affected with the cachectic dwarfism of Cockayne syndrome. Fibroblast cultures derived from these patients exhibited increased sensitivity to ultraviolet (UV) light, but not to x-irradiation, as measured by colony-forming ability. In both Cockayne fibroblast cultures, the rate of removal of thymidine dimer from the irradiated cellular DNA was normal. This demonstration of a cellular defect in Cockayne cells suggests that there may be an enzymatic defect in the repair of UV light-induced damage.
mesh_terms: D000015:Abnormalities, Multiple / Q000378:metabolism; D002675:Child, Preschool; D002906:Chromosomes, Human, 6-12 and X; D004392:Dwarfism / Q000150:complications / Q000378:metabolism*; D005260:Female; D005347:Fibroblasts / Q000378:metabolism / Q000528:radiation effects; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008607:Intellectual Disability / Q000150:complications; D008297:Male; D010787:Photosensitivity Disorders / Q000150:complications / Q000378:metabolism*; D013577:Syndrome; D013936:Thymidine / Q000378:metabolism; D014314:Trisomy; D014466:Ultraviolet Rays
chemical_list: D013936:Thymidine