Cockayne syndrome (CS) is an autosomal recessive disorder characterized by dwarfism, growth deficiency, neurological deterioration, skin photosensitivity and a characteristic progressive facial appearance. In the present study we report the first Brazilian CS family in which diagnosis was confirmed by the demonstration of decreased RNA synthesis in cultured fibroblasts exposed to UV-C radiation. Despite the progressive course of the disease and the unavailability of an effective treatment, diagnosis may be very important for the benefits to be gained by the afflicted family from genetic counseling and/or prenatal diagnosis.
