D. Martin Carter

Low-sulfur hair syndrome associated with UVB photosensitivity and testicular failure

A 16-year-old male patient had a syndrome that included growth retardation, mental retardation, hair shaft abnormalities, neurosensory hearing loss, contractures of the fifth fingers, ultraviolet B (UVB) photosensitivity, small testicular size, and elevated levels of follicle-stimulating hormone. Reduced hair sulfur content and a characteristic pattern of light and dark birefringent bands, seen when hairs were viewed with polarization microscopy, were typical of the low-sulfur hair syndrome. UVB photosensitivity and testicular failure have not previously been identified as components of this syndrome.

SISTER CHROMATID EXCHANGES IN DYSKERATOSIS CONGENITA AFTER EXPOSURE TO TRIMETHYL PSORALEN AND UV LIGHT

ABSTRACT Exposure in vitro of cultivated peripheral leukocytes to trimethylpsoralen and UV light (365nm) under conditions that are known to produce DNA cross-links caused a greater increase in the number of sister chromatid exchanges in cells from two patients with dyskeratosis congenita (DKC) than in normal cells. Absence of this enhancing phenomenon in an unaffected sibling of one patient as well as its presence to a partial degree in an obligate carrier suggest that the observation may be etiologically significant. The data suggest that DKC is associated with a heritable defect in the repair of DNA cross-links.