The present invention relates to variant of Family A polymerases able to synthesize a nucleic acid fragment without template and to incorporate a reversible modified terminator nucleotide during the nucleic acid fragment synthesis. The present invention further relates to uses thereof for enzymatic synthesis of nucleic acid molecules.

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.

Provided in the present invention is an enzyme reaction solution for constructing a sequencing library and the use thereof. The enzyme reaction solution comprises an enzyme composition and a reaction buffer, wherein the enzyme composition comprises a nucleic acid endonuclease, a DNA polymerase, and a polynucleotide kinase; and the reaction buffer comprises a metal salt, a substrate, and a buffer medium aqueous solution. The present application aims to optimize the formulation of an enzyme reaction solution. The cleavage, terminal repair and addition of A to the terminal of a nucleic acid sample is achieved by a one-step reaction. In a suitable buffer system, the enzyme digestion reaction rate and the terminal repair reaction rate reach a balance. In the case where the initial amount of the sample is 100 pg to 1 .Math.g and the processing time is the same, a sequencing library with a consistent length distribution is obtained.

The present disclosure relates to engineered DNA polymerase polypeptides and compositions thereof, as well as polynucleotides encoding the engineered DNA polymerase polypeptides. The present disclosure also provides methods of using the engineered DNA polymerase polypeptides or compositions thereof for diagnostic and other purposes.

High-fidelity, high-throughput nucleic acid sequencing enables healthcare practitioners and patients to gain insight into genetic variants and potential health risks. However, previous methods of nucleic acid sequencing often introduces sequencing errors (for example, mutations that arise during the preparation of a nucleic acid library, during amplification, or sequencing). Provided herein are sequencing adapters comprising a nondegenerate or variable length molecular barcode and compositions comprising a plurality of sequencing adapters, which can be useful for sequencing nucleic acids. Further provided are methods of using the sequencing adapters, including methods of sequencing nucleic acids, methods of identifying an error in a nucleic acid sequence, and methods of determining the number of nucleic acid molecules in a library.

Disclosed are mutant DNA polymerases having increased 3′-mismatch discrimination relative to a corresponding, unmodified polymerase. The mutant polymerases are useful in a variety of disclosed primer extension methods. Also disclosed are related compositions, including recombinant nucleic acids, vectors, and host cells, which are useful, e.g., for production of the mutant DNA polymerases.

Fusion polypeptides having a heterologous 5′-3′ exonuclease domain linked to a polymerase that does not naturally have 5′-3′ exonuclease activity, as well as methods of their use are provided. Other aspects are also disclosed.

The disclosure provides systems, methods, and compositions for a target specific nuclease and a blunting enzyme to correct frameshift mutations for genome editing and treatment of diseases. In some embodiments, the target specific nuclease and the blunting enzyme are combined with a guide RNA and/or a microhomology-mediated end joining (MMEJ) inhibitor.

Disclosed are mutant DNA polymerases having increased 3′-mismatch discrimination relative to a corresponding, unmodified polymerase. The mutant polymerases are useful in a variety of disclosed primer extension methods. Also disclosed are related compositions, including recombinant nucleic acids, vectors, and host cells, which are useful, e.g., for production of the mutant DNA polymerases.

The invention relates to constructs comprising a transmembrane protein pore subunit and a nucleic acid handling enzyme. The pore subunit is covalently attached to the enzyme such that both the subunit and enzyme retain their activity. The constructs can be used to generate transmembrane protein pores having a nucleic acid handling enzyme attached thereto. Such pores are particularly useful for sequencing nucleic acids. The enzyme handles the nucleic acid in such a way that the pore can detect its component nucleotides by stochastic sensing.