Patent ID: 7468244
Filing Date: 2008-12-23
Classification: C12Q

Abstract:
1. A method of distinguishing the presence of a nonsupercoiled target nucleic acid from the presence of nonsupercoiled target variants within a sample of nucleic acids having a common target query region, the method comprising: providing a first oligonucleotide and a second oligonucleotide, wherein said first oligonucleotides is bound by a recombinase and said second oligonucleotide is free of a recombinase; adding said first oligonucleotide to the sample to form a mixture; adding said second oligonucleotide to the mixture to form a double D loop; deproteinizing the double D loop; and distinguishing the double D loops that are stable to deproteinization, wherein the presence of a stable double D loop distinguishes the presence of target from that of variants; wherein the first oligonucleotide comprises a complementarity region that is perfectly complementary to a first strand of the target across the entirety of the target query region and wherein the second oligonucleotide includes a complementarity region that is perfectly complementary in sequence to a second strand of the target across at least a portion of the target query region, and at least one of said first or second oligonucleotide complementarity regions is imperfectly complementary to at least one of a first strand or a second strand of the query region of the target variants.