[Study of the mechanism of mutagenesis directed by phosphotriester analogs of oligonucleotides. The role of repair in mutagenesis].

The mutation system has been suggested in an effort to test insertion and deletion mutants by changing the Lac-phenotype of bacterial colonies transformed by mutant DNA. This system also makes possible to determine heterozygotes and homozygotes among the mutants. The yield of mutants in shown to depend on the structure of the DNA heteroduplex region. The yield of deletion mutants is greater than that of insertion mutants. Heterozygotes prevail in mutant colonies (greater than 90%).