Sequencing method and apparatus

• US 7,133,782 B2
• Filed: 07/02/2001
• Issued: 11/07/2006
• Est. Priority Date: 07/05/2000
• Status: Expired due to Fees

• Current Assignee: GE Healthcare UK Limited (Danaher Corporation)
• Original Assignee: GE Healthcare UK Limited (Danaher Corporation)
• Inventors: Odedra, Raj
• Primary Examiner(s): Brusca, John S.
• Application Number:
  US10/312,048
• Publication Number:
  US 20030186276A1
• Time in Patent Office: 1,954 Days
• Field of Search: None
• US Class Current: 702/20
• CPC Class Codes: G16B 30/00 ICT specially adapted for sequence analysis involving nucleotides or amino acids
• CPC Class Codes: G16B 30/20 Sequence assembly

Abstract

In a method of identifying an unknown nucleotide sequence using base addition, a sequence of bases is obtained from a template, a base in the sequence is identified as an unknown base, an “unknown” indicator is included in the sequence, and an output sequence is generated containing the unknown base indicator. The sequence of bases is obtained from the template by evaluation of a reporter and assigning the bases in accordance therewith. A determination is made as to whether the reporter is from a preceding cycle of base determination, and if the reporter is from a preceding cycle of base determination, the base assignation is discarded.

Claims

1. A method for obtaining maximally contiguous nucleic acid sequence from a nucleic acid sequencing reaction wherein an immobilized primer-template complex is extended enzymically utilizing one or more reporter moiety-labelled nucleotides as said enzyme substrate, comprising the steps of:

a) determining whether said reporter moiety is detectable and corresponds with the location of said primer-template complex;

b) in the absence of any reporter moiety signal corresponding to the location of the primer-template complex, recording a pause for the corresponding primer-template complex and incrementing a corresponding pause counter;

c) if the pause counter, incremented for a given primer-template complex, exceeds a predetermined threshold, deeming the base preceding the first of the consecutive pauses a mismatch and marking the base corresponding to that location accordingly in the sequence,

d) if a reporter moiety is detected following step a), recording the corresponding base and assigning said base to the sequence of the said primer-template complex and setting the pause counter to zero,

e) eliminating the reporter moiety attached to any incorporated base, and

f) repeating steps a) to e) until the sequencing reaction is complete.

2. The method of claim 1, wherein the nucleic acid sequence is annotated to mark the locations in the sequence where a reporter moiety was not detected to indicate the potential for a gap in the sequence.

3. The method of claim 1, wherein said signal is rejected if the reporter moiety detected is from the preceding base addition and has failed to eliminate in step e).

4. The method of claim 1, further comprising the step of determining the location of the template by detecting the location of the reporter moiety on the incorporated base.

5. The method of claim 1, further comprising the step of determining the location of the template by detecting the location of a reporter moiety attached to the primer-template complex that is distinguishable from any reporter moiety present on the reporter-labelled base nucleotide.

6. The method of claim 1, wherein the location is determined by the co-location of the reporter moiety on the incorporated labelled base and the reporter moiety attached to the primer-template complex which is distinguishable from those corresponding to the reporter-labelled base nucleotide.

7. The method of claim 1, wherein the primer in the primer-template complex is covalently attached to the template.

8. The method of claim 1, wherein the enzyme is a nucleic acid polymerase.

9. The method of claim 1, wherein the enzyme is a nucleic acid ligase.

10. The method of claim 9, wherein the reaction is performed with enzyme substrates comprising two or more ligated bases.

11. The method of claim 1, wherein the reporter moiety is selected from the group consisting of isotope, radioisotope, enzyme, hapten, fluorophore, chromophore, chemiluminescent group, Raman label and electrochemical label.

12. The method of claim 11, wherein the reporter moiety is a fluorophore.

13. The method of claim 1, wherein the reporter-labelled nucleotide comprises one or more of the bases A, G, C and T.

14. The method of claim 1, wherein the reporter-labelled nucleotide comprise one or more of the bases A, G, C and U.

15. A computer program code on computer readable media for performing all of the steps of claim 1, when said program is run on a computer.