Genetic and Clinical Study of Patients With Xeroderma Pigmentosum, Cockayne Syndrome, or Trichothiodystrophy

OBJECTIVES:

- Identify patients or confirm suspected cases of xeroderma pigmentosum (XP), Cockayne
syndrome (CS), XP/CS, or trichothiodystrophy (TTD).

- Document presence or absence of cancers (skin, eye, tongue, or internal) in these
patients.

- Document atypical features or unusual environmental exposures of these patients.

- Examine tissue (skin, blood, hair, or buccal swabs) from these patients and their first
degree relatives for DNA repair and genetic analysis.

- Identify molecular defects in the DNA repair genes in cells from these patients and
correlate the defects with clinical features.

- Follow the clinical course of selected patients.

OUTLINE: Patients are evaluated initially by phone, followed by a complete history and
physical exam, including appropriate clinical and laboratory tests.

Tissue (skin, blood, buccal swabs, or hair) is obtained for laboratory studies of the
effects of DNA damage, measurement of DNA repair, genetic analysis of DNA, and/or assessment
of immunologic abnormalities.

If malignancies are detected during examinations and tissue collections, patients are
referred for treatment. Genetic counseling is also available.

Patients are followed annually.

PROJECTED ACCRUAL: A total of 500 patients will be accrued for this study.