ABSTRACT
Cockayne syndrome is a rare autosomal recessive disorder with dwarfism, mental retardation, and otherwise clinically heterogeneous features. Classically, the onset of Cockayne syndrome starts in the second year of life. The failure of RNA synthesis to recover to normal rates after UV-C irradiation provides a useful diagnostic test and the clinical feature that correlates most strongly with defective RNA synthesis is photosensitivity. To report an unusual case of Cockayne Syndrome. A case of a five-year-old girl with Cockayne with an onset in early infancy the girl and without photosensitivity is presented. The diagnosis was confirmed by the failure of RNA synthesis to recover to normal rate after UV-C irradiation. The patient died at the age of 6 of pneumonia. Although rare, Cockayne syndrome may be presented without photosensitivity and had an early onset