ANALYSIS OF ELECTROPORATION-INDUCED GENETIC DAMAGES IN V79 AP4 CHINESE-HAMSTER CELLS/

Electroporation is a recent technique used to introduce exogenous DNA into eukaryotic cells. It is important to establish that the gene of i nterest is transferred into a functional, non-mutated recipient cell. V79/AP4 Chinese hamster cells were exposed to high-voltage pulsed elec tric fields and some biological and genetic effects were measured. The results showed that cytotoxicity was related in a dose-dependent mann er to the number of applied pulses. Thioguanine-resistant colony-formi ng cells as well as chromosomal aberrations were also induced whereas ouabain resistants and sister-chromatid exchanges were not or slightly induced. Spontaneous and electroporation-induced clones that were phe notypically TG(R)/HAT(S) were used to investigate the hprt locus. Mole cular screening of the locus showed that the number of deleted exons w as significantly higher in induced than in spontaneous TG-resistant cl ones, suggesting that the genetic damages induced by electroporation c oncern the loss of regions well over the size of the hprt locus.