Ways to amplify GC rich fragment?

[Andrew Leung]

Hi all,

    I am going to amplify a 1 kb fragment which has 70% GC in content and
with obvious repeated GC stretch. Now, the problem is I can't get it
amplified. Is there any suggestion in this case?

    Specifically, primers I tried has about 60% GC, annealing temperature
61C and with a rather standard PCR condition.

    How should I modify my PCR condition? Thank you.

Andrew