Megaprimer PCR

[Csaba Jeney]

We are trying to get a PCR product using a very long primer pair (60bp
each, 20 bp anealing length) but until now there is nothing to glad.
We already have changed the annealing temperature, the Mg
concentration and the next step will be the primer concentration.
Could anybody out there suggest other things and/or suggest the ranges
of these variables to get of rid this problem.

Thank you in advance.

Csaba