FISH multicolour background

Gordon Munro g_munro at
Mon Mar 10 04:03:03 EST 1997

Gahtani <M.H.Algahtani at> wrote:

>I am dong multicolour FISH Exp. on lymphoma chrmosome metaphases ( 
>patients and cell lines) using Teaxes Red and FITC ( direct and indirect 
>tech,) but the problem which I am facing know is the background 
>specially with FITC, larg and tiny green dots all over the slides
>please, I need any help to cont. my work, S who has the magic answer.
>looking to read your answer on my e-mail.

Large and tiny green dots all over the slides is either due to the
probe being too large (large dots) or using gloves which have powder
on them (small dots).Both of these cuase background mainly on the
slides,  not on the cells.   Cellular background could well be caused
by endogenous biotin in the cells if you are using the indirect
detection system.

If probes are too large,  then careful DNAsing or sonication of the
probe may help.  If you are labelling by nick translation try running
out your probe on a gel to check whether you have the optimal 300 to
500 bp size range.

Martin Lawrie
Chromoprobe development manager
Cytocell Ltd

probes at

Gordon Munro            email:  g_munro at
Cytocell Ltd

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Opinions expressed are my own and not necessarily those of Cytocell Ltd.

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