Cockayne syndrome type A(redirected from progeroid nanism)
Cockayne syndrome type AA rare disorder (OMIM:216400) characterised by cutaneous sensitivity to sunlight, abnormal and slow growth, cachectic dwarfism, progeroid appearance, progressive pigmentary retinopathy, sensorineural deafness, delayed neural development, and severe progressive neurologic degeneration resulting in mental retardation. Cockayne syndrome shows some overlap with certain forms of xeroderma pigmentosum; unlike xeroderma pigmentosum, patients with Cockayne syndrome do not manifest increased freckling and other pigmentation abnormalities in the skin and have no significant increase in skin cancer.
• Cockayne syndrome type A (or type 1; “classical” form)—Progressive symptoms apparent within the first few years of life.
• Cockayne syndrome type B (or type 2)—Severe symptoms that manifest prenatally.
Defects of ERCC8, which encodes a protein involved in transcription-coupled nucleotide excision repair, cause Cockayne syndrome type A.