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Hotstart in PCR - (Dec/16/2004 )


We have seen in a "bisulfite treatment of DNA" protocol that they use a HOTSTART polymerase in the PCR reaction after the purification of the treated sample.

Could anyone tell us why is it recommend instead of the normal Taq polymerase?

Thank you!


It has to do with reduction of nonspecific bands due to the inherent low specificity of primers for bisulfite treated DNA (long strings of Ts). I've also seen that you should use a polymerase without proofreading capabilities- I don't really know why that is, but maybe just because of the strange sequence that you have. I use faststart from roche-- it works well and is even one of their cheapest polymerases.

Using hotstart PCR is a really common suggestion, so I'd say just go with it and don't question! It's not hard to do.