Abstract <p>Methods for correcting errors in synthetic oligonucleotides and genetic constructs derived from them are described. Methods for isolating oligonucleotides with a perfect structure from oligonucleotide pools are discussed. Methods for correcting errors in the DNA structure using mismatch-specific endonucleases and proteins of the bacterial DNA repair system are considered. Examples of practical application of the methods developed for adjusting the structure of synthesized genetic constructs are given.</p>