Patent ID: 7629152

Claim:
A method for amplifying a nucleotide sequence of interest in a nucleic acid polymer, which method comprises: (a) contacting the nucleic acid polymer with a primer set comprising a plurality of non-replicable primers and a plurality of replicable primers, to form a reaction mixture in which, (i) each of the non-replicable primers comprises modified structures that a polymerase catalyzing an extension reaction cannot copy, and is capable of hybridizing to the nucleic acid polymer and forming a first primer extension product using the nucleic acid polymer as a template, said first primer extension product comprising the modified structures of the non-replicable primer and at least a portion of the nucleotide sequence of interest or its complement, and (ii) each of the replicable primers is capable of hybridizing to the first primer extension product and forming a second primer extension product using the first primer extension product as a template, wherein the extension of the second primer-extension product terminates at the modified structures of the first primer extension product such that the second primer extension product does not contain a sufficiently complementary sequence to hybridize with the non-replicable primer and form a first primer extension product; (b) subjecting the reaction mixture to conditions such that (i) the non-replicable primer hybridizes to the nucleic acid polymer and forms the first primer extension product, and (ii) the replicable primer hybridizes to the first primer extension product to form the second primer extension product; (c) separating the first and second primer extension products from the nucleic acid polymer templates and treating the resulting mixture with the primer set under conditions such that additional first and second primer extension products are produced; and (d) repeating step (c) to provide a reaction mixture wherein the at least a portion of the nucleotide sequence of interest or its complement is amplified polynomially.