[Polymerase chain reaction and ligase reactions. Principles, traditional methods, and innovations]

The polymerase chain reaction (PCR) is a favorite among the diagnostic DNA probes. Besides the traditional PCR scheme, the author considers the new strictly quantitative modifications representing a combination of PCR with semiautomated immunoassay, this simplifying the practical use of the method. Errors most frequently occurring in PCR are discussed. The ligase chain reaction, more rapid than PCR, and permitting one to obtain a billion of DNA molecule copies in 30 min, is described, and prospects of its use for rapid diagnosis shown.