[Ideal gene therapy: approaches and prospects].

Ideal gene therapy implies correction of a genetic mutation at the site of its localization on the chromosome. This can be done only with homologous recombination. In prokaryotes, two mechanisms of homologous recombination are provided by two types of recombinases, an ATP-dependent RecA protein and an ATP-independent renaturase. In eukaryotes both the ATP-dependent and ATP-independent DNA transferases have been revealed, among which functionally RecA-like enzymes were also found. The unique properties of RecA-like proteins suggest that these enzymes promote recombination both in pro- and eukaryotes. According to recent observations, the mitotic eukaryotic cells do possess a potential for homologous recombination. However to realize it the donor DNA should be reasonably long and be maximally homologous to the recipient DNA. Other possibilities of optimizing the gene therapy process are discussed.