Human Genetics

, Volume 74, Issue 2, pp 107–112

Xeroderma pigmentosum (complementation group D) mutation is present in patients affected by trichothiodystrophy with photosensitivity


  • M. Stefanini
    • Istituto di Genetica Biochimica ed Evoluzionistica CNR
  • P. Lagomarsini
    • Istituto di Genetica Biochimica ed Evoluzionistica CNR
  • C. F. Arlett
    • MRC Cell Mutation Unit University of Sussex, Falmer
  • S. Marinoni
    • Istituto per l'Infanzia
  • C. Borrone
    • Istituto G. Gaslini Div. Pediatrica III
  • F. Crovato
    • Divisione DermatologicaOspedale Chiavari
  • G. Trevisan
    • Clinica DermatologicaUniversità Trieste
  • G. Cordone
    • Istituto Clinica Pediatrica IUniversità Genova
  • F. Nuzzo
    • Istituto di Genetica Biochimica ed Evoluzionistica CNR
Original Investigations

DOI: 10.1007/BF00282072

Cite this article as:
Stefanini, M., Lagomarsini, P., Arlett, C.F. et al. Hum Genet (1986) 74: 107. doi:10.1007/BF00282072


We studied the response to UV irradiation in cells from four patients, from three apparently unrelated families, affected by trichothiodystrophy (TTD). They showed all the symptoms of this rare autosomal recessive disorder (brittle hair with reduced sulfur content, mental and physical retardation, ichthyosis, peculiar face) together with photosensitivity. We found a decreased rate of duplicative DNA synthesis in stimulated lymphocytes, reduced survival in fibroblasts, and very low levels of unscheduled DNA synthesis (UDS) in Go lymphocytes and fibroblasts after UV irradiation. Complementation studies showed that normal values of UDS are restored in heterokaryons obtained by fusion of TTD cells with normal and xeroderma pigmentosum (XP)-complementation group A-cells. In contrast the defect is not complemented by fusion with XP-complementation group D-fibroblasts.

Copyright information

© Springer-Verlag 1986