Biotinylated PCR primers

[Nir Navot]

As the question of using biotinylated PCR primers arose, I remembered a strange
artifact that we were getting when we used a biotinylated PCR primer - in the
"no DNA" control we would get a very strong smear from about 5 kb down. In the
reactions where there was DNA we would get a nice and specific band. No smear,
nothing else. Does anybody have any idea as to what could cause such a smear?
The student   who got these results attributed the smear to the viscosity of
the biotinylated primer solution. Any comments??

Thanks in advance,
Nir Navot

The Weizmann Institute of Science
Rehovot, Israel.
LCNAVOT at WEIZMANN