Method of Sequencing a Genome
A method and computer-program product for sequencing nucleic acid sequences using restriction fragment maps derived from end-sequenced nucleotide fragments. The initial nucleotide sequence can be processed to form a shot-gun-data set. The present teachings employ a technique called Restriction Site Shotgun Sequencing (RSSS.) It can reduce the amount of overlap required between fragment ends while still producing a good assembly. A decrease in overlap can be achieved by using additional information in the fragments to assist in determining that two fragments overlap.
1 . A method for determining the sequence of a nucleotide sequence comprising,
generating one or more sets of nucleotide fragments from said nucleotide sequence,
generating one or more sets of end-sequenced fragments by sequencing the ends of the fragments in said one or more sets of nucleotide fragments,
generating one or more sets of restriction-digested fragments by restriction digesting said one or more sets of end-sequenced fragments,
generating one or more tiling sets of fragments from said one or more sets of restriction-digested fragments,
tiling said one or more tiling sets of fragments to form one or more restriction fragment maps,
determining the sequence of said nucleotide sequence by collapsing said one or more restriction fragment maps and aligning sequence information corresponding to the sequenced ends of the fragments in said one or more sets of end-sequenced nucleotides fragments.
2 . The method of claim one wherein said first set of nucleotide fragments is generated by random shearing.
3 . The method of claim one wherein said first set of nucleotide fragments is generated by partial digestion.
4 . The method of claim one further comprising filtering said set of nucleotide fragments in order to select fragments within one or more user-defined size ranges.
5 . The method of claim 4 further comprising determining the size of the fragments in said tiling set of fragments.
6 . The method of claim 5 wherein said determining comprises
performing a single base extension reaction on said tiling set of fragments,
forming a mixture by combining the product of said single-base extension reaction with the product of a sequencing reaction wherein the ddNTPs in the single-base extension are labeled with different dyes than those used in the single-base extension reaction, and
running said mixture in a separation medium.
7 . The method of claim one further comprising,
determining a total length of shared sizes between a first set of restriction-digested fragments and a second set of restriction-digested fragments, and
forming a tiling set of fragments consisting of the fragments from said first and second set of restriction-digested fragments if the total length of shared sequences exceeds a user-defined threshold.
8 . A program storage device readable by a machine, embodying a program of instructions executable by the machine to perform method steps for determining the sequence of a nucleotide sequence comprising,
receiving information regarding one or more sets of nucleotide fragments from said nucleotide sequence,
receiving information regarding one or more sets of end-sequenced fragments derived from said one or more sets of nucleotide fragments,
receiving information regarding one or more sets of restriction-digested fragments derived from said one or more sets of end-sequenced nucleotide fragments,
generating one or more tiling sets of fragments from said one or more sets of restriction-digested fragments,
tiling said one or more tiling sets of fragments to form one or more restriction fragment maps,
determining the sequence of said nucleotide sequence by collapsing said one or more restriction fragment maps and aligning sequence information corresponding to the sequenced ends of the fragments in said one or more sets of end-sequenced nucleotides fragments.
9 . The program storage of claim eight further comprising filtering said set of nucleotide fragments in order to select fragments within one or more user-defined size ranges.
10 . The method of claim eight further comprising,
determining a total length of shared sizes between a first set of restriction-digested fragments and a second set of restriction-digested fragments, and
forming a tiling set of fragments consisting of the fragments from said first and second set of restriction-digested fragments if the total length of shared sequences exceeds a user-defined threshold.