Detection of nucleic acid differences using combined endonuclease cleavage and ligation reactions
First Claim
1. A method for identifying a mutant nucleic acid sequence differing by one or more single-base changes, insertions, or deletions, from a normal target nucleotide sequences, said method comprising:
- providing a sample potentially containing the normal target nucleotide sequence as well as the mutant nucleic acid sequence;
providing two labeled oligonucleotide primers suitable for hybridization on complementary strands of the target nucleotide sequence and the mutant nucleic acid sequence;
providing a polymerase;
blending the sample, the labeled oligonucleotide primers, and the polymerase to form a polymerase chain reaction mixture;
subjecting the polymerase chain reaction mixture to one or more polymerase chain reaction cycles comprising a hybridization treatment, wherein oligonucleotide primers hybridize to the target nucleotide sequence and/or the mutant nucleic acid sequence, an extension treatment, wherein the hybridized oligonucleotide primer is extended to form an extension product complementary to the target nucleotide sequence and/or the mutant nucleic acid sequence to which the oligonucleotide primer is hybridized, and a denaturation treatment, wherein hybridized nucleic acid sequences are separated;
inactivating the polymerase;
denaturing the polymerase chain reaction extension products;
annealing the polymerase chain reaction extension products to form heteroduplexed products potentially containing the normal target nucleotide sequence and the mutant nucleic acid sequence;
providing an endonuclease which preferentially nicks or cleaves heteroduplexed DNA at a location one base away from mismatched base pairs;
blending the heteroduplexed products and the endonuclease to form an endonuclease cleavage reaction mixture;
incubating the endonuclease cleavage reaction mixture so that the endonuclease preferentially nicks or cleaves heteroduplexed products at a location one base away from mismatched base pairs;
providing a ligase;
blending the potentially nicked or cleaved heteroduplexed products and the ligase to form a ligase resealing reaction mixture;
incubating the ligase resealing reaction mixture to seal the nicked heteroduplexed products at perfectly matched base pairs but with substantially no resealing of nicked heteroduplexed products at locations adjacent to mismatched base pairs;
separating products resulting from said incubating the ligase resealing reaction mixture by size or electrophoretic mobility; and
detecting the presence of the normal target nucleotide sequence and the mutant nucleic acid sequence in the sample by distinguishing the separated products resulting from said incubating the ligase resealing reaction mixture.
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Abstract
The present invention is a method for detecting DNA sequence differences including single nucleotide mutations or polymorphisms, one or more nucleotide insertions, and one or more nucleotide deletions. Labeled heteroduplex PCR fragments containing base mismatches are prepared. Endonuclease cleaves the heteroduplex PCR fragments both at the position containing the variation (one or more mismatched bases) and to a lesser extent, at non-variant (perfectly matched) positions. Ligation of the cleavage products with a DNA ligase corrects non-variant cleavages and thus substantially reduces background. This is then followed by a detection step in which the reaction products are detected, and the position of the sequence variations are determined.
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Citations
83 Claims
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1. A method for identifying a mutant nucleic acid sequence differing by one or more single-base changes, insertions, or deletions, from a normal target nucleotide sequences, said method comprising:
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providing a sample potentially containing the normal target nucleotide sequence as well as the mutant nucleic acid sequence; providing two labeled oligonucleotide primers suitable for hybridization on complementary strands of the target nucleotide sequence and the mutant nucleic acid sequence; providing a polymerase; blending the sample, the labeled oligonucleotide primers, and the polymerase to form a polymerase chain reaction mixture; subjecting the polymerase chain reaction mixture to one or more polymerase chain reaction cycles comprising a hybridization treatment, wherein oligonucleotide primers hybridize to the target nucleotide sequence and/or the mutant nucleic acid sequence, an extension treatment, wherein the hybridized oligonucleotide primer is extended to form an extension product complementary to the target nucleotide sequence and/or the mutant nucleic acid sequence to which the oligonucleotide primer is hybridized, and a denaturation treatment, wherein hybridized nucleic acid sequences are separated; inactivating the polymerase; denaturing the polymerase chain reaction extension products; annealing the polymerase chain reaction extension products to form heteroduplexed products potentially containing the normal target nucleotide sequence and the mutant nucleic acid sequence; providing an endonuclease which preferentially nicks or cleaves heteroduplexed DNA at a location one base away from mismatched base pairs; blending the heteroduplexed products and the endonuclease to form an endonuclease cleavage reaction mixture; incubating the endonuclease cleavage reaction mixture so that the endonuclease preferentially nicks or cleaves heteroduplexed products at a location one base away from mismatched base pairs; providing a ligase; blending the potentially nicked or cleaved heteroduplexed products and the ligase to form a ligase resealing reaction mixture; incubating the ligase resealing reaction mixture to seal the nicked heteroduplexed products at perfectly matched base pairs but with substantially no resealing of nicked heteroduplexed products at locations adjacent to mismatched base pairs; separating products resulting from said incubating the ligase resealing reaction mixture by size or electrophoretic mobility; and detecting the presence of the normal target nucleotide sequence and the mutant nucleic acid sequence in the sample by distinguishing the separated products resulting from said incubating the ligase resealing reaction mixture. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41)
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42. A method for identifying a mutant nucleic sequence differing by one or more single-base changes, insertions, or deletions from a normal target nucleic acid sequence, said method comprising:
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providing a sample potentially containing the mutant nucleic acid sequence but not necessarily the normal target nucleic acid sequence; providing a standard containing the normal target nucleic acid sequence; providing two labeled oligonucleotide primers suitable for hybridization on complementary strands of the mutant nucleic acid sequence; providing a polymerase; blending the sample, the standard, the labeled oligonucleotide primers, and the polymerase to form a first polymerase chain reaction mixture; subjecting the first polymerase chain reaction mixture to one or more polymerase chain reaction cycles comprising a hybridization treatment, wherein the labeled oligonucleotide primers hybridize to the mutant nucleic acid sequence, an extension treatment, wherein the hybridized oligonucleotide primer is extended to form an extension product complementary to the mutant nucleic acid sequence to which the oligonucleotide primer is hybridized, and a denaturation treatment, wherein hybridized nucleic acid sequences are separated; inactivating the polymerase; providing the normal target nucleic acid sequence; blending the normal target nucleic acid sequence, the labeled oligonucleotide primers, and the polymerase to form a second polymerase chain reaction mixture; subjecting the second polymerase chain reaction mixture to one or more polymerase chain reaction cycles comprising a hybridization treatment, wherein the labeled oligonucleotide primers hybridize to the normal target nucleic acid sequence, an extension treatment, wherein the hybridized oligonucleotide primer is extended to form an extension product complementary to the normal target nucleic acid sequence to which the oligonucleotide primer is hybridized, and a denaturation treatment, wherein hybridized nucleic acid sequences are separated; inactivating the polymerase; blending the first and second polymerase chain reaction extension products; denaturing the first and second polymerase chain reaction extension products; annealing the first and second polymerase chain reaction extension products to form heteroduplexed products potentially containing the normal target nucleic acid sequence and the mutant nucleic acid sequence; providing an endonuclease which preferentially nicks or cleaves heteroduplexed DNA at a location one base away from mismatched base pairs; blending the heteroduplexed products and the endonuclease to form an endonuclease cleavage reaction mixture; incubating the endonuclease cleavage reaction mixture so that the endonuclease preferentially nicks or cleaves heteroduplexed products at a location one base away from mismatched base pairs; providing a ligase; blending the potentially nicked or cleaved heteroduplexed products and the ligase to form a ligase resealing reaction mixture; incubating the ligase resealing reaction mixture to seal the nicked heteroduplexed products at perfectly matched base pairs but with substantially no resealing of nicked heteroduplexed products at locations adjacent to mismatched base pairs; separating products resulting from said incubating the ligase resealing reaction mixture by size or electrophoretic mobility; and detecting the presence of the normal target nucleic acid sequence and the mutant nucleic acid sequence target nucleotide in the sample by distinguishing the separated products resulting from said incubating the ligase resealing reaction mixture. - View Dependent Claims (43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82)
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83. A method for identifying a mutant nucleic acid sequence differing by one or more single-base changes, insertions, or deletions, from a normal target nucleic acid sequence, said method comprising:
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providing a sample potentially containing the normal target nucleic acid sequence as well as the mutant nucleic acid sequence; providing two labeled oligonucleotide primers suitable for hybridization on complementary strands of the target nucleic acid sequence and the mutant nucleic acid sequence; providing a polymerase; blending the sample, the labeled oligonucleotide primers, and the polymerase to form a polymerase chain reaction mixture; subjecting the polymerase chain reaction mixture to one or more polymerase chain reaction cycles comprising a hybridization treatment, wherein oligonucleotide primers hybridize to the target nucleic acid sequence and/or the mutant nucleic acid sequence, an extension treatment, wherein the hybridized oligonucleotide primer is extended to form an extension product complementary to the target nucleic acid sequence and/or the mutant nucleic acid sequence to which the oligonucleotide primer is hybridized, and a denaturation treatment, wherein hybridized nucleic acid sequences are separated; inactivating the polymerase; denaturing the polymerase chain reaction extension products; annealing the polymerase chain reaction extension products to form heteroduplexed products potentially containing the normal target nucleic acid sequence and the mutant nucleic acid sequence; providing an endonuclease which preferentially nicks or cleaves heteroduplexed DNA at a location one base away from mismatched base pairs; blending the heteroduplexed products and the endonuclease to form an endonuclease cleavage reaction mixture; incubating the endonuclease cleavage reaction mixture so that the endonuclease preferentially nicks or cleaves heteroduplexed products at a location one base away from mismatched base pairs; providing a ligase; blending the potentially nicked or cleaved heteroduplexed products and the ligase to form a ligase resealing reaction mixture; incubating the ligase resealing reaction mixture to seal the nicked heteroduplexed products at perfectly matched base pairs but with substantially no resealing of nicked heteroduplexed products at locations adjacent to mismatched base pairs; providing a polymerase with 3′
-5′
exonuclease activity;blending the potentially nicked or cleaved heteroduplexed products and the polymerase with 3′
-5′
exonuclease activity to form a polymerase exonucleolytic degradation reaction mixture;incubating the polymerase exonucleolytic degradation reaction mixture under conditions effective for the 3′
-5′
exonucleolytic activity to remove several bases 3′
to the nick;inactivating the polymerase with 3′
-5′
exonuclease activity;providing a polymerase without 3′
-5′
activity;blending the incubated polymerase degradation reaction mixture, the polymerase without 3′
-5′
activity, labeled dideoxyterminator triphosphate nucleotides, and deoxyribonucleotide triphsophates to form a polymerase mini-sequencing reaction mixture;incubating the polymerase mini-sequencing reaction mixture under conditions effective for the polymerase without 3′
-5′
activity to extend the 3′
end of the nicked or cleaved heteroduplexed products to form mini-sequencing reaction products;separating the mini-sequencing products by size or electrophoretic mobility; and detecting the presence of normal target nucleic acid sequence and the mutant nucleic acid sequence by distinguishing the separated mini-sequencing products resulting from said incubating the polymerase mini-sequencing reaction mixture.
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Specification