Monitoring of induced chromosomal aberrations in S. cerevisiae in agarose gels by pulsed field gel electrophoresis.

Pulsed field gel electrophoresis (PFGE) has been used to detect aberrations of the chromosomal banding pattern referred to as chromosomal aberrations arising after treatment of yeast strain S. cerevisiae MP1 with the three different genotoxic substances 4-nitroquinoline-N-oxide (4-NQO), methotrexate (MTX) and 2-amino-6-mercaptopurine (AMP). Different chromosomal aberrations were detectable directly in the pulsed field gel when growing yeast cells were incubated with a genotoxin for 6 h at 26 degrees C followed by treatment with the genotoxin for another twelve days at 4 degrees C. In the present study, clones of yeast cells were examined. In this way, distinct chromosomal aberrations and not only DNA smear could be detected. Moreover, this method allows selection for yeast strains with specific and rare chromosomal rearrangements.