pfau at tarleton.edu ("Russell S. Pfau") wrote in message news:<B797250C.9A7%pfau at tarleton.edu>...
> I've recently begun using a 20cm x 20cm x 1.5mm polyacrylamide gel format
> for SSCP and microsatellite analyses. Two things have happened regarding
> the appearance of the DNA size standards that I can't explain, and I'm
> wondering if anyone else can.
>> One size standard, a 100 bp ladder from New England Biolabs, exhibits bands
> that are not separating as they normally should. For example, with this
> size standard there are bands of the following lengths: 400 bp, 300 bp, 200
> bp, 100 bp, but the 300 and 200 bp bands may be *closer* together than the
> 400 and 300 bp bands, the opposite of what should be true. Also, some of
> the bands are missing! From what I can tell, bands 1517 & 1200 are not
> there at all!
>> The other size standard I'm using, a 25 bp ladder, exhibits quadruplets!
> Four bands for each size category.
>> Images of my gels can be viewed here:
>>http://www.tarleton.edu/~biology/pfau/images/odd_bands.htm>> Can anyone explain this?
>> Thanks in advance for any insight,
>> Russell
>> ---
Russell,
for SSCP you'd running a non denaturing acrylamide gel which may
interfere with the running of your size standards. do you think this
may be having an effect?
Nick
