Radiation-induced damage, repair and exchange formation in different chromosomes of human fibroblasts determined by fluorescence in situ hybridization

Journal Article · Sat Jan 01 04:00:00 EST 1994 · Radiation Research

DOI:https://doi.org/10.2307/3578788· OSTI ID:45264

Kovacs, M S; Evans, J W; Johnstone, I M; Brown, J M ^[1]

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1. Stanford Univ., CA (United States)

We have used fluorescence in situ hybridization with whole-chromosome probes for human chromosomes 1, 4, 8 and 13 to investigate the extent to which the induction of damage and its repair after exposure to ionizing radiation is distributed randomly among these chromosomes. All the studies were performed with AG1522 human fibroblasts irradiated with 6 Gy and maintained in a nondividing state for at least 6 h after irradiation except for the measurements of initial damage. The extent of initial damage was determined by fusion of the cells immediately after irradiation with metaphase HeLa cells to obtain premature chromosome condensation (PCC). Breaks and exchanges were also scored by PCC 24 h after irradiation and in metaphase spreads at the first division after irradiation. The data obtained were consistent with random breakage and repair in these chromosomes. Comparing PCC 24 h after irradiation with first metaphase, there was a deficit in aberrations at metaphase, particularly in unrejoined breaks, implying loss or slowing of cells containing aberrations prior to the first division. An analysis of dicentrics and translocations in chromosome 4 at first and in subsequent divisions showed that there was an equal number of dicentrics and translocations at first metaphase with loss of dicentrics, but no loss of translocations in subsequent divisions. These data are supportive of the hypothesis that the total number of chromosome aberrations in cells can be estimated from a single chromosome pair. 34 refs., 5 figs., 2 tabs.

• Sponsoring Organization: USDOE
• OSTI ID: 45264
• Journal Information: Radiation Research, Journal Name: Radiation Research Journal Issue: 1 Vol. 137; ISSN RAREAE; ISSN 0033-7587
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
BIOLOGICAL REPAIR
CHROMOSOMAL ABERRATIONS
CHROMOSOME BREAKAGE
FIBROBLASTS
FLUORESCENCE
HELA CELLS
HUMAN CHROMOSOME 1
HUMAN CHROMOSOME 13
HUMAN CHROMOSOME 8
HUMAN CHROMOSOMES
IONIZING RADIATIONS
RADIATION INJURIES
RADIOINDUCTION