Analysis of radiation-induced micronuclei in two-cell human-hamster embryos using telomeric and centromeric FISH probes.

Department de Biologia Cel.lular i Fisiologia, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Cytogenetics and cell genetics 02/1996; 74(1-2):102-6. DOI: 10.1159/000134392
Source: PubMed

ABSTRACT Simultaneous, fluorescent in situ hybridization using a centromeric human alpha satellite DNA probe and a telomeric DNA probe was used to analyze the chromosome content of micronuclei induced in two-cell human-hamster embryos by in vitro gamma-ray irradiation of human spermatozoa. In unirradiated samples, about 26% of micronuclei were centromere positive, indicating that both structural chromosome aberrations and numerical changes are involved in the spontaneous production of micronuclei. After exposure of spermatozoa to radiation, a significant increase in the number of micronuclei was found. About 77% of induced micronuclei contained only telomeric signals suggesting that they originated from acentric fragments. However, both centromere-positive and centromere-negative micronuclei increased with radiation dose. These results are consistent with the well known clastogenic effect of ionizing radiation and with its weak aneugenic effect.

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Laura Tusell