spurious large products seen following RT-PCR

[drodenhi at julian.uwo.ca]

When performing RT-PCR, has anyone observed a continuous smear of spurious
products all of which are larger than the predicted PCR product, which is
also still present? (The spurious bands form a continuous "smear" above
the expected band.) The smear can also be defined as discrete bands as the
PCR conditions are optimized. Thanks for any explanations and/or ways to
eliminate this problem.