i screened many DNA samples extracted from the cervical brush sample for presence or absence of HPV DNA with primer set GP5+ /6+ and i got five positive sample. then i used that 5 positive samples to amplify with PGMY9/11 primer set but none of them gave any band on gel. so any one has any idea how to get amplification or protocol of PCR reaction and temperature cycling, then please let me inform.
Does your positive control give a good band. If not then you may have a primer degradation or annealing temperature problem. If you are not running a positive control sample then there are many possible answers to tis question
Paul is right. The result from your positive control is critical. Use HPV16 if you can and make a dilution series so that you can evaluate the performance of the reaction. Use human DNA as a diluent if you have any available; it gives a more realistic estimate of analytical sensitivity.
That said, the GP+ and PGMY primers probably have varying analytical sensitivity for different HPV types, so it is entirely possible for some types to be detectable with one primer set and undetectable with the other.
Another trick you can use to check your result is to spike an aliquot of your sample with (e.g.) HPV16 and run PCR. If your spiked sample is positive and the unspiked sample is negative then your sample is a true PGMY negative.
Finally: do check that your GP bands are the right size. Cross-reactions do happen, particularly with consensus primers.
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