How to determine the DNA sequence without sequencing? - (Oct/16/2006 )

Hi, I am just currious - does anybody of you know if there is except for sequencing any other technique that enables determination of the exact sequence of DNA?

Thank you for any help.

Paja

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Partly with restriction enzymes making a restriction map, but it is very partly.

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http://www.georgiasouthern.edu/~jyzhang/maldi-tof.html
interesting. but quite expensive...

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sequencing means to determine a sequence, I mean to determine each base in a strand; nowadays, its a routine technique done by university facilities or companies, it is not that expansive; any other method than classical sequencing will be more complicated or even more expensive;

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Moreover, if it worked, it would be called "sequencing".

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as long as u want to know the sequence , and any method which gives u the sequence will b called sequencing.

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well if you mean aside from Sanger sequencing method....

there is pyro sequencing, the 454 method uses this.

there is chemical degredation... (can't for the life i me, remember its name) It is an old traditional method, preceeding sanger sequencing.

there is direct sequencing using polymerase and modified dNTP that stop the polymerase at each
step, and give off a light upon excitation, degrades and allow the next round of dNTP addition.
there is

there is sequencing by nanopore method... threading a DNA strand through a hole in a silicon waffer and reading the voltage change to detemine nucleotide identity

there is malditof sequencing method

there is sequencing by annealing to large oligo on chips.

there is the polony sequencing method

I can't remember any other more methods right now...

of the above example only Pyrophosphate sequencing method has made it to commercial use. But it is limited to only 300bp reads at maximum... average reads are 100bp only.

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Thank you all guys,
your comments were very helpful. Just for an explanation - I am writing a paper and I got stuck on the sentence "... sequencing is the only one technique that enables determination of the exact DNA sequence (each base in a strand)..." I didn't want to put there some nonsence.
Thanks once more.

Paja

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If you need such as sentence to define what sequencing mean, I would prefer to write:

"sequencing is a technique that enables determination of the exact DNA sequence (each base in a strand)..."

your definition implies that there may be a doubts about the singularity of the method; of course, there are different techniques to sequence DNA but sequencing is that what the sentence says

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