Patent ID: 7468245
Filing Date: 2008-12-23
Classification: C12P,C12Q

Abstract:
1. A process for detecting the presence of a specific target nucleic acid sequence comprising the steps of: 1) providing one or more first initial primers or first initial nucleic acid constructs comprising at least two segments: wherein the portion of said specific target nucleic acid sequence that comprises sequences identical to the second segment of the first initial primer or initial nucleic acid construct and the portion of said specific target nucleic acid sequence that comprises sequences complementary to the first segment of said first initial primer or first initial nucleic acid construct are in close proximity to each other on said specific target nucleic acid sequence; 2) providing at least one second initial primer or second initial nucleic acid construct, wherein (i) said second initial primer or second initial nucleic acid construct comprises a first segment sufficiently complementary to said first primer extension to bind or hybridize thereto, (ii) wherein said second initial primer or second initial nucleic acid construct is nonidentical to said first initial primer or first initial nucleic acid construct (iii) wherein said first segment provides for template dependent primer extension such that a second primer extension is produced and (iv) wherein said second initial primer or second initial nucleic acid construction further comprises a second segment being (a) non-identical to the first segment of said second initial primer or said second initial primer construct and (b) sufficiently complementary to sequences primer or second initial nucleic acid construct with said first primer isothermal conditions; 3) mixing said first initial primer or first initial nucleic acid construct and said second initial primer or second initial nucleic acid construct with substrates, buffer, a template-dependent polymerizing enzyme and a sample to be tested for the presence of said specific target nucleic acid sequence; 4) incubating said mixture under isostatic or limited cycling conditions, extension of said first initial primers or first initial nucleic acid constructs; 5) forming at least one stem-loop structure by separating said first segment of said first initial primer or first initial nucleic acid construct from said specific target nucleic acid sequences by self-annealing between said second segment of said first initial primer or first initial nucleic acid construct and a segment formed after target template dependent extension of the first segment of said first initial primer or first initial nucleic acid construct and 6) detecting the presence of said stem-loop structures formed in said forming step (5), thereby detecting the presence of said specific target nucleic acid sequence or its complement.