Stupid Question regarding PCR

Robert Horton horton at
Thu Sep 14 12:07:13 EST 1995

Richard Rohan (rrohan at wrote:
: Sami Kohan <skohan at> wrote:

: >Why is it standard to use DNA oligonucleotides in PCR when in vivo, when
: >DNA is replicating, the polymerase use RNA primers?

: Probably because the chemistry for synthesis of DNA oligos is much easier and
: thus RNA oligos are more expensive or possibly not available when commercial
: PCR was developed.  I vaguely recall that in Dupont's "prior art" suit against
: PCR they cited something in the original taq polymerase papers that closely
: resembled PCR except using tRNA primers. 

Using RNA primers would require an RNA-dependant DNA polymerase activity 
for use in PCR.

RNA is also not very stable when heated in the presence of magnesium.

Does anybody have a reference for the papers mentioned?

Robert M. Horton (PhD!) /\ "Crash programs fail because of the theory that
U of M Dermatology Dept || with nine women pregnant you get a baby a month"
Box 98 UMHC, 4-154 PWB /||\ -W. von Braun.   Disclaimer: "Bob who?"
Minneapolis, MN 55455   ^^   horton at       (612)625-8941

More information about the Methods mailing list