METHOD FOR AMPLIFYING SPECIFIC NUCLEIC ACID FRAGMENTS WITH THE AID OF A RECURRENT CHAIN REACTION

The invention relates to a method for amplifying specific nucleic acid fragments with the aid of two variants of a recurrent chain reaction 2/2 and 2/1, in which instead of the typical primers used in a standard PCR, the primers in the form of tandem repeated sequences of a singular (basic) primer, in which repeats are disposed according to a "head-to-tail" type, and which consist of two or more such elements, are used as forward and/or reverse primers. As a result of amplification, the length of an amplicon is increased with each cycle by the length of the singular primer, thereby increasing, over a cycle, annealing places in the amplicon, providing the growth of the coefficient of replication and bringing about the accelerated accumulation of the amplicons, the number of which is greater by several orders than said number in a PCR. The use of a thermostable Vent-type DNA polymerase exhibiting DNA strand displacement activity results in a double-stranded amplicon being produced in each cycle and results in the single-stranded DNA which are formed before the annealed primers and are displaced by said polymerase, the number of such amplicons in the form of single-stranded DNA increasing in each cycle. The inventive method can be recommended for sequencing DNA, for DNA diagnostics in medicine, veterinary science, in sanitary and epidemiological studies, in the food industry for detecting food products made from genetically modified organisms, for testing raw material quality, for detecting the agents of dangerous infections, including potential bio-terrorist attacks, and in criminalistics for identifying criminals.