The invention relates to the development and optimization of PCR and RT-PCR systems used to detect nucleic acids, including the diagnosis of genetic, viral, and other diseases. The essence of the proposed method is that neutral derivatives of oligonucleotides, namely phosphoryl guanidines containing one or more phosphate groups in which guanidine or substituted guanidine residue is introduced on the phosphorus atom, are used as primers for the template-based amplification, including polymerase chain reaction (PCR) and PCR combined with reverse transcription (RT-PCR). The invention allows to obtain more reliable, specific and selective results in the process of PCR, in particular, to increase the sensitivity of PCR by reducing the yield of by-products of DNA amplification and/or to control the yield of the PCR product, including intentionally suppressing, by using different combinations of the location and number of modified phosphate groups in the oligonucleotide primers.

Oligonucleotide constructs are described, each comprising a functional element and a coding element, wherein the functional element comprises a functional sequence, the functional sequence comprising a sequence of nucleotides in which one or more, or each, nucleotide is modified and the coding element comprises a coding sequence, the coding sequence comprising a sequence of nucleotides which do not contain the modifications of the functional sequence, wherein the coding sequence encodes the sequence structure of the functional sequence.

Oligonucleotide constructs are described, each comprising a functional element and a coding element, wherein the functional element comprises a functional sequence, the functional sequence comprising a sequence of nucleotides in which one or more, or each, nucleotide is modified and the coding element comprises a coding sequence, the coding sequence comprising a sequence of nucleotides which do not contain the modifications of the functional sequence, wherein the coding sequence encodes the sequence structure of the functional sequence.

Provided are systems, kits, and methods for the quantitative detection of single nucleotide polymorphisms or variants to identify malignant neoplasms. The methods include use of modified oligonucleotide blockers with peptide nucleic acid backbones that hybridize to and block logarithmic amplification of the wild-type alleles of a target, and incorporation of locked nucleic acids into probes that are complementary to a mutant allele of the target sequence to increase specificity. The methods include detection of variants in sequences with high GC content and/or low complexity, such as the TERT promoter, IDH1, BRAF, NRAS, GNAQ, GNA11 and H3F3 A gene variants. The methods include sensitive detection and staging of cancers with low cellularity, and can be used intraoperatively such as for glioma, or to detect cell-free circulating tumor DNA, such as for melanoma.

Provided are systems, kits, and methods for the quantitative detection of single nucleotide polymorphisms or variants to identify malignant neoplasms. The methods include use of modified oligonucleotide blockers with peptide nucleic acid backbones that hybridize to and block logarithmic amplification of the wild-type alleles of a target, and incorporation of locked nucleic acids into probes that are complementary to a mutant allele of the target sequence to increase specificity. The methods include detection of variants in sequences with high GC content and/or low complexity, such as the TERT promoter, IDH1, BRAF, NRAS, GNAQ, GNA11 and H3F3 A gene variants. The methods include sensitive detection and staging of cancers with low cellularity, and can be used intraoperatively such as for glioma, or to detect cell-free circulating tumor DNA, such as for melanoma.

Nucleotide triphosphate probes containing a molecular and/or atomic tag on a γ and/or β phosphate group and/or a base moiety having a detectable property are disclosed, and kits and method for using the tagged nucleotides in sequencing reactions and various assay. Also, phosphate and polyphosphate molecular fidelity altering agents are disclosed.

Nucleotide triphosphate probes containing a molecular and/or atomic tag on a γ and/or β phosphate group and/or a base moiety having a detectable property are disclosed, and kits and method for using the tagged nucleotides in sequencing reactions and various assay. Also, phosphate and polyphosphate molecular fidelity altering agents are disclosed.

The present invention relates to sequencing probes, methods, kits, and apparatuses that provide enzyme-free, amplification-free, and library-free nucleic acid sequencing that has long-read-lengths and with low error rate.

The present invention relates to sequencing probes, methods, kits, and apparatuses that provide enzyme-free, amplification-free, and library-free nucleic acid sequencing that has long-read-lengths and with low error rate.

A method of ligating DNA molecules, wherein the DNA molecules are in a hybrid with an RNA molecule, including the steps of providing DNA molecules that are in a RNA:DNA hybrid with an RNA molecule, and ligating the DNA molecules to each other with a double strand specific ligase