Analysis of restriction enzyme-induced chromosomal aberrations by fluorescence in situ hybridization.
Fluorescence in situ hybridization and Giemsa staining of metaphase chromosomes were used to determine the relative frequencies of symmetric exchange aberrations (translocations) and asymmetric exchange aberrations (rings, dicentrics, and polycentrics) after exposure of human lymphoblastoid cells to restriction enzymes or X-rays. The yield of symmetric exchanges was determined with the use of chromosome-specific probes for human chromosomes 2 or 4, which were hybridized to metaphase chromosomes from cells exposed to the enzymes PvuII, SacI, or XbaI or 3 or 5 Gy of X-rays. The yield of asymmetric exchanges was determined in Giemsa-stained metaphase chromosomes from the same enzyme-treated or irradiated cell population. About 1.5- to 3-fold more symmetric than asymmetric exchanges were induced after restriction enzyme treatment. However, after X-ray treatment the yield of dicentrics relative to the yield of reciprocal translocations was close to the expected 1:1 ratio.
Abella Columna
E
E
Laboratory of Radiobiology and Environmental Health, University of California, San Francisco 94143-0750.
Giaccia
A J
AJ
Evans
J W
JW
Yates
B L
BL
Morgan
W F
WF
D002460:Cell Line; D002869:Chromosome Aberrations; D002872:Chromosome Deletion; D002889:Chromosomes, Human, Pair 2; D002894:Chromosomes, Human, Pair 4; D004249:DNA Damage / Q000187:drug effects* / Q000528:radiation effects*; D004262:DNA Restriction Enzymes / Q000494:pharmacology*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D012303:Ring Chromosomes; D014178:Translocation, Genetic; D014965:X-Rays
D004262:DNA Restriction Enzymes