False positive - help - (Jun/13/2014 )

Hi.
As a newcomer to the forum i would greatly appreciate any help anyone could offer. I am running PCR to amplify approx 150bp sequence. I am getting a strong band on gel for the pos control isolate but other isolates, which I know should be not be positive, are giving fainter but definite bands at same 150bp position as pos control. However, my negative control is negative. Can anyone shed any light on what could be going on? Thanks

Or those samples aren't negative as you thought or the amplification band that you are seen isn't the target and are unspecify amplification

change the primer you used, it not suitable for your experiment. you could get the primer sequence from   http://pga.mgh.harvard.edu/primerbank/   or re-design them

change the primer you used, it not suitable for your experiment. you could get the primer sequence from   http://pga.mgh.harvard.edu/primerbank/   or re-design them