tk at pasteur.ai.mit.edu
Tue Sep 12 19:58:10 EST 2000
VERGARAC at naos.si.edu ("Carlos Vergara") writes:
You may have too much template DNA in your sequencing reaction. Lots
of DNA drives the reaction quickly for the first bases, but there is
little reagent left for later bases. Try reducing the amount of
template DNA by 5x or more and see what happens.
> We have been experiencing problems with our ABI 377. Over the last
> weeks, we have seen a continual decline in our sequencing samples
> quality gave short sequences that the signals decreased after 300
> bp. We are using good DNA template extracted by phenol/chlorophorm
> method, very well PCR products purified from low melting point
> agarose gel with gelase, and cycle sequencing products cleaned by
> sephadex columns. Recently, our ABI 377 was checked and no found it
> technical problems.
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