Accelerated sequencing methods
Described herein are methods of generating a coupled sequencing read pair for a polynucleotide, and methods of analyzing the coupled sequencing read pair. The coupled sequencing read pair can be analyzed to detect polynucleotide variants, including at loci that are not directly sequenced within the coupled sequencing read pair. Other analytical methods can include using coupled sequencing read pairs to construct or validate a consensus sequence. The coupled sequencing read pair may be generated for a polynucleotide by generating sequencing data for a first region by extending a primer using labeled nucleotides; further extending the primer through a second region using nucleotides provided in a second region flow order, wherein primer extension through the second region is faster than primer extension through the first region; and generating sequencing data associated with a sequence of a third region of the polynucleotide by further extending the primer using labeled nucleotides.
1. A method of sequencing, comprising:
(a) sequencing a first region of a nucleic acid molecule by, in each flow step of a plurality of first flow cycles, incorporating and detecting a labeled nucleotide, or detecting lack of incorporation thereof, into a primer hybridized to the nucleic acid molecule, wherein nucleotides used in each flow step of the plurality of first flow cycles comprises a mixture of labeled and unlabeled nucleotides;
(b) extending the primer through a second region of the nucleic acid molecule by, in at least one flow step of a plurality of second flow cycles, incorporating nucleotides of a mixture of two or three different types of nucleotide bases into the primer, without detecting incorporation of the nucleotides, wherein the plurality of second flow cycles is different from the plurality of first flow cycles; and
(c) sequencing a third region of the nucleic acid molecule by, in each flow step of a plurality of third flow cycles, incorporating and detecting a labeled nucleotide, or detecting lack of incorporation thereof, into the primer, wherein the plurality of third flow cycles is different from the plurality of second flow cycles.
2. The method of claim 1 , wherein a fewer number of flow cycles are performed to extend the primer through an equivalent length of the second region than the first region of the nucleic acid molecule.
3. The method of claim 1 , wherein a fewer number of flow steps are performed to extend the primer through an equivalent length of the second region than the first region of the nucleic acid molecule.
4. A method of sequencing, comprising:
(a) extending a primer hybridized to a nucleic acid molecule through a first region of the nucleic acid molecule, by, in at least one flow step of a plurality of first flow cycles, incorporating a nucleotide into the primer (i) without detecting incorporation of the nucleotide into the primer, and (ii) wherein, a mixture of two or three different types of nucleotide bases are provided for incorporation into the primer; and
(b) sequencing a second region of the nucleic acid molecule by, in each flow step of a plurality of second flow cycles, incorporating and detecting a labeled nucleotide, or detecting lack of incorporation thereof, into the primer, wherein the plurality of first flow cycles is different from the plurality of second flow cycles; and wherein nucleotides used in each flow step of the plurality of second flow cycles comprises a mixture of labeled and unlabeled nucleotides.
5. The method of claim 4 , further comprising, prior to (a), hybridizing the primer at a naturally occurring sequence of the nucleic acid molecule.
6. The method of claim 1 , wherein (b) comprises, in each flow step of the plurality of second flow cycles, incorporating nucleotides of the mixture for said flow step into the primer, without detecting incorporation of the nucleotides.
7. The method claim 1 , wherein at least a portion of a plurality of nucleotides used to extend the primer through the second region are unlabeled nucleotides.
8. The method of claim 1 , wherein each nucleotide used to extend the primer through the second region is an unlabeled nucleotide.
9. The method of claim 1 , wherein the plurality of second flow cycles comprises at least two flow cycles.
10. The method of claim 9 , wherein the plurality of second flow cycles comprises at least five flow steps.
11. The method of claim 1 , wherein each flow step of the plurality of first flow cycles comprises a single nucleotide base type.
12. The method of claim 1 , wherein the plurality of second flow cycles comprises 4 separate flow steps repeated in the same order.
13. The method of claim 1 , wherein the plurality of second flow cycles comprises a first flow cycle and a second flow cycle different from the first flow cycle.
14. The method of claim 1 , wherein sequencing the nucleic acid molecule further comprises:
extending the primer through a fourth region of the nucleic acid molecule by, in at least one flow step of a plurality of fourth flow cycles different from the plurality of first flow cycles, incorporating nucleotides of a mixture of at least two different types of nucleotide bases into the primer, without detecting incorporation of the nucleotides; and
sequencing a fifth region of the nucleic acid molecule by, in each flow step of the plurality of third flow cycles different from the plurality of second flow cycles, incorporating and detecting a labeled nucleotide, or detecting lack of incorporation thereof, into the primer.
15. The method of claim 1 , wherein the nucleic acid molecule is amplified using rolling circle amplification.
16. The method claim 4 , wherein at least a portion of a plurality of nucleotides used to extend the primer through the first region are unlabeled nucleotides.
17. The method of claim 4 , wherein each nucleotide used to extend the primer through the first region is an unlabeled nucleotide.
18. The method of claim 4 , wherein the plurality of first flow cycles comprises five or more flow steps.
19. The method of claim 18 , wherein each of the five or more flow steps comprises a single nucleotide base type.
20. The method of claim 4 , wherein the plurality of first flow cycles comprises 4 separate flows repeated in the same order.
21. The method of claim 4 , wherein the plurality of first flow cycles comprises a first flow cycle and a second flow cycle different from the first flow cycle.
22. The method of claim 4 , wherein the nucleic acid molecule is amplified using rolling circle amplification.