AFLP Problem - Smearing

[Elena Maria Dimuzio]

<fontfamily><param>Geneva</param><bigger><bigger>Hello,


I am experiencing problems with AFLPs.  My reactions were working
beautifully last summer.  I have just started doing them again (using
the same pre-amplified DNA) and I'm seeing the same basic patterns on
the gel in terms of major and minor bands, but the major bands are
smearing - instead of resolving into a sharp band, they leave a little
tail behind them in the gel.  It looks like hair streaming back from
the band. The minor bands are also much less intense then they were
before.  I know the template DNA I'm using is ok, and Life Tech sent me
a new kit which they've had no complaints about for the primers and PCR
buffer.  I thought it was the gel, and have gotten new reagents for all
the gel components, but it doesn't seem to matter - I still have the
same problem.  Has anyone encountered anything like this before? 
Again, I have changed all the PAGE gel components with no success.  
Another strange fact is that the AFLP ladder on the gels seems to run
just fine, a little bit blurry maybe but not big streaking like I see
in the sample lanes (even with the Life Tech pre-amplified DNA).


Thanks for your help.


Elena DiMuzio

Cornell University

emd15 at cornell.edu

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