Methods for sequencing polynucleotides
Provided herein is a method for sequencing a polynucleotide molecules. The method includes the steps of providing a plurality of polynucleotide molecules attached to a surface, wherein a first portion of each polynucleotide molecule is attached to a first location of the surface and a second portion of each polynucleotide molecule is attached to a second location of the surface, the relative proximity of the first and second locations being correlated with the probability that the first and second portions are paired, separating the first and second portions of the polynucleotide molecules on the surface, determining the sequences of the first and second portions of the polynucleotide molecules and comparing the relative proximities and the sequences to determine which first and second portions are paired and to determine the sequence of the target polynucleotide molecules.
1. A method for determining sequences of polynucleotides that potentially contain a first portion and a second portion from the same polynucleotide, comprising:
(a) providing a plurality of polynucleotides attached to a surface, wherein each of the plurality of polynucleotides comprises a first portion, a second portion, and a region between the first portion and the second portion, the end of the first portion of each of the polynucleotides is attached to one location of the surface and the end of the second portion of each of the polynucleotides is attached to another location of the surface, and wherein each of the plurality of polynucleotides has a known length;
(b) separating the first portion of each of the polynucleotides from the second portion of each of the polynucleotides by cleaving the region between the first portion of each of the polynucleotides and the second portion of each of the polynucleotides;
(c) after step (b), determining a probability of the first portion attached to which location of the surface and the second portion attached to which location of the surface are derived from the same polynucleotide by comparing a distance between the location on the surface which the first portion of each of the polynucleotides is attached to and the location on the surface which the second portion of each of the polynucleotides is attached to with the known length of each of the plurality of polynucleotides, thereby assembling polynucleotides that potentially contain the first portion and the second portion from the same polynucleotide;
(d) sequencing the first portion of each of the plurality of polynucleotides and the second portion of each of the plurality of polynucleotides; and
(e) determining the sequences of the polynucleotides that potentially contain the first portion and the second portion from the same polynucleotide based on the results from steps (c) and (d).
2. The method of claim 1 , wherein the known length of each of the plurality of polynucleotides is within a range of sizes.
3. The method of claim 1 , wherein the plurality of polynucleotides is double-stranded.
4. The method of claim 1 , wherein the first portion and the second portion are noncontiguous.
5. The method of claim 1 , wherein each of the first portion and the second portion comprises an indexing tag.
6. The method of claim 5 , wherein the first portion and the second portion of the same polynucleotide comprise the same indexing tag.
7. The method of claim 1 , wherein the surface is a patterned surface comprising a first population of oligonucleotides and a second population of oligonucleotides.
8. The method of claim 1 , wherein step (b) comprises contacting the plurality of polynucleotides with a transposase and the region between the first portion and the second portion comprises a transposon.
9. The method of claim 1 , wherein step (b) comprises cleaving each of the plurality of polynucleotides at a cleavable site located on the region between the first portion and the second portion.
10. The method of claim 9 , wherein the cleavable site comprises a modified nucleotide or a restriction enzyme site.
11. The method of claim 9 , wherein the cleavage site comprises a uracil residue or derivative thereof.
12. The method of claim 11 , wherein step (b) comprises contacting each of the plurality of polynucleotides with a uracil DNA glycosylase (UDG).
13. The method of claim 1 , wherein step (b) further comprises amplifying the first portion and the second portion.
14. The method of claim 1 , wherein step (c) comprises identifying the location on the surface which the first portion of each of the polynucleotides is attached to and the location on the surface which the second portion of each of the polynucleotides is attached to using an imaging device.
15. The method of claim 1 , wherein step (d) is performed using sequencing by ligation, sequencing by synthesis, or sequencing by hybridization.
16. The method of claim 1 , wherein step (d) is performed prior to step (c).
17. The method of claim 1 , further comprising comparing the sequence of the first portion of each of the plurality of polynucleotides and the sequence of the second portion of each of the plurality of polynucleotides with a reference sequence.
18. The method of claim 1 , wherein the surface is a surface of a flow cell.
19. The method of claim 1 , wherein step (a) comprises: producing fragments by fragmenting a genomic DNA, adding adaptors to the ends of the fragments, thereby obtaining the plurality of polynucleotides.