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PCR issue - (Mar/19/2009 )

Hi!

Iam getting a strange gel picture for my PCR results. The wells that have a correct product are fine but the wells with weak or no product have a smear, including negative control! Iam wondering that if this is some kind of contamination, then why the lanes with correct product doesnŽt have the smears? The setup was following - I put genomic DNA in the bottom of wells (~100-150ng) and then added mastermix (buffer with MgCl2, primers, dNTPs, enzyme and water). Negative control was without DNA. Total reaction volume 25ul. Soon I try to post a gel picture also!

Best regards,
Peeter

-scn-

Here is the gel picture also. An arrow indicates the negative control.

Peeter
Attached Image

-scn-

Hi Peeter,

It looks like a potential degraded DNA contamination in any of your PCR components. The smear in sample lanes might be due to the same degraded DNA. you dont see the smear in the sample wells becos, the degraded DNA might have been used up for the amplification. in other wells it might not. I hope im correct.

better to discard the PCR components and use new for further reactions.

Kif

scn on Mar 19 2009, 08:15 AM said:

Here is the gel picture also. An arrow indicates the negative control.

Peeter

-kifayath-