Patent ID: 8252558

Claim:
A method for amplifying and optionally detecting a target sequence of a nucleic acid of interest in a sample, wherein the nucleic acid of interest comprises one strand or two separate complementary strands, the method comprising the steps of: (a) treating the sample with at least two oligonucleotide primers capable of hybridizing to a first strand of the target sequence, at least one oligonucleotide primer capable of hybridizing to a second strand of the target sequence complementary to the first strand, wherein the at least two primers for the first strand of the target sequence comprises one outer primer and one or more inner primers, wherein outer primer and inner primer hybridize to the first strand of the target sequence so that the 3′ end of the outer primer points toward the 5′ end of the inner primer, wherein the treating is carried out under hybridizing and extension conditions such that an extension product of each primer is synthesized complementary to its hybridizing strand of the target sequence if present; (b) separating the primer extension products from templates to produce single-stranded molecules; (c) treating the single-stranded molecules generated from step (b) with the primers of step (a) under hybridizing and extension conditions such that a primer extension product is synthesized using some or all of the single stranded molecules produced in step (b) as a template; and (d) repeating steps (b) and (c) at least once, wherein one or more of said inner primers is a linker-primer, which linker-primer comprises a linker so that a single-stranded end product is accumulated, wherein the outer primer or each outer primer is not a linker-primer, and wherein the extension conditions are such that the primer extension product of an inner primer is displaced by the primer extension product of an outer primer.