Southern analysis in transgenic plant

[Bryan J. Maloney]

In article <48109c29.0106300917.281a8be5 at posting.google.com>, 
crystal.ann at gurlmail.com (Ann) wrote:

> Can anyone help me to explain my southern result? Why did I can detect
> the presence of the gene in some part of the plant BUT I can't do so
> in some part of the plant. I took the samples from the leaves. Isn't
> it means that transgenic plants will have the presence of the gene all
> over the part? Can it be the other way round? By the way , I did
> detect the presence of the gene in all the samples via PCR method.
> Please explain to me. Thank you very much


Possible explanations:

Different contaminants from different tissues interfering with parts of 
the assay.

Each tissue requires a different extraction, which means that it might 
be as simple as a bit of organic solvent contaminating some samples and 
not others.

Uneven transfer from the gel onto the blot.

Some combination of the above.

How many times have you tried to repeat the Southern from fresh plant 
tissue?

-- 
"A 'Cape Cod Salsa' just isn't right."