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Wed Nov 25 23:24:10 EST 1992

In article <01GRKOX8SIFK001160 at> Wei Shao,
>I am trying to clone a gene from lambda gt11 expression library with a
>oligonucleotide probe. Usually, one has to make a set of duplicates of
>nitrocellulose filter to confirm the spots are real. I heard that
>duplicates are not really reliable. Is this true?
It's not strictly true, and if the hyb conditions are reproduced then the
duplicate plaque spots should light up.  Make sure you have the duplicate
filters in the same hybridization bag (or whatever).  At the very least,
you should always do a secondary screen of positive plaques.  Having
duplicate filters in the primary screen will make you feel a lot more
confident about getting a postive result the second time around.
  Good luck.
                 Eamonn Gormley, E.P.Gormley at

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