Enhanced G2 chromatid radiosensitivity in dyskeratosis congenita fibroblasts

Journal Article · Thu Feb 01 04:00:00 EST 1990 · American Journal of Human Genetics; (USA)

OSTI ID:7190174

DeBauche, D M; Pai, G S; Stanley, W S ^[1]

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1. Medical Univ. of South Carolina, Charleston (USA)

Dyskeratosis congenita (DC) is an inherited disorder characterized by reticular pigmentation of the skin, dystrophic nails, mucosal leukoplakia, and a predisposition to cancer in early adult life. In the majority of cases, DC is an X-linked recessive trait. However, one or more autosomal form(s) of DC may exist. Although excessive spontaneous chromatid breakage has been reported in DC, it is not a consistent cytological marker for this disorder. We examined the frequency and specificity of X-irradiation-induced G2 chromatid breakage in fibroblasts from three unrelated DC patients (two males and one female). Metaphase cells from DC patients had significantly more chromatid breaks (16-18-fold and 17-26-fold at 50 and 100 rad X-irradiation, respectively) and chromatid gaps (10-12-fold and 6-7-fold at 50 and 100 rad, respectively) than those from two different controls. Analysis of banded chromosomes revealed a nonrandom distribution of chromatid aberrations in DC but not in controls, a distribution corresponding to some of the known breakpoints for cancer-specific rearrangements, constitutive fragile sites, and/or loci for cellular proto-oncogenes. The significance of this finding for cancer predisposition in DC patients is uncertain, but the increased susceptibility of X-irradiation-induced chromatid breakage may serve as a cellular marker of diagnostic value.

• OSTI ID: 7190174
• Journal Information: American Journal of Human Genetics; (USA), Journal Name: American Journal of Human Genetics; (USA) Vol. 46:2; ISSN AJHGA; ISSN 0002-9297
• Country of Publication: United States
• Language: English

Related Subjects

560120* -- Radiation Effects on Biochemicals
Cells
& Tissue Culture
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMAL CELLS
BIOLOGICAL EFFECTS
BIOLOGICAL MARKERS
BIOLOGICAL RADIATION EFFECTS
CELL TRANSFORMATIONS
CHROMATIDS
CHROMOSOMAL ABERRATIONS
CONGENITAL DISEASES
CONNECTIVE TISSUE CELLS
DISEASES
ELECTROMAGNETIC RADIATION
FIBROBLASTS
GENETIC EFFECTS
GENETIC RADIATION EFFECTS
IONIZING RADIATIONS
MUTATIONS
ONCOGENIC TRANSFORMATIONS
RADIATION EFFECTS
RADIATIONS
RADIOINDUCTION
SOMATIC CELLS
X RADIATION